Variabel adalah sesuatu yang memiliki nilai yang dapat berubah. Dalam istilah paling sederhana, variabel hanyalah sebuah kotak tempat Anda dapat memasukkan barang. Anda dapat menggunakan variabel untuk menyimpan semua jenis barang, tetapi untuk saat ini, kita hanya akan melihat cara menyimpan angka dalam variabel
Kode ini membuat variabel yang disebut red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _9, dan memberikannya bilangan bulat >>> print ('I am a single quoted string') I am a single quoted string >>> print ("I am a double quoted string") I am a double quoted string >>> print ("""I am a triple quoted string""") I am a triple quoted string 0. Saat kami meminta Python untuk memberi tahu kami apa yang disimpan dalam variabel red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 9, itu mengembalikan nomor itu lagi
Kita juga bisa mengubah apa yang ada di dalam variabel. Sebagai contoh
changing = 3 print (changing) 3 changing = 9 print (changing) 9 different = 12 print (different) 12 print (changing) 9 changing = 15 print (changing) 15
Kami mendeklarasikan variabel yang disebut >>> print ('I am a single quoted string') I am a single quoted string >>> print ("I am a double quoted string") I am a double quoted string >>> print ("""I am a triple quoted string""") I am a triple quoted string _2, memasukkan bilangan bulat >>> print ('I am a single quoted string') I am a single quoted string >>> print ("I am a double quoted string") I am a double quoted string >>> print ("""I am a triple quoted string""") I am a triple quoted string 3 di dalamnya, dan memverifikasi bahwa penugasan telah dilakukan dengan benar. Kemudian, kami menetapkan bilangan bulat >>> print ('I am a single quoted string') I am a single quoted string >>> print ("I am a double quoted string") I am a double quoted string >>> print ("""I am a triple quoted string""") I am a triple quoted string _4 ke >>> print ('I am a single quoted string') I am a single quoted string >>> print ("I am a double quoted string") I am a double quoted string >>> print ("""I am a triple quoted string""") I am a triple quoted string 2, dan tanyakan lagi apa yang disimpan di >>> print ('I am a single quoted string') I am a single quoted string >>> print ("I am a double quoted string") I am a double quoted string >>> print ("""I am a triple quoted string""") I am a triple quoted string 2. Python telah membuang >>> print ('I am a single quoted string') I am a single quoted string >>> print ("I am a double quoted string") I am a double quoted string >>> print ("""I am a triple quoted string""") I am a triple quoted string _3, dan menggantinya dengan >>> print ('I am a single quoted string') I am a single quoted string >>> print ("I am a double quoted string") I am a double quoted string >>> print ("""I am a triple quoted string""") I am a triple quoted string 4. Selanjutnya, kita membuat variabel kedua, yang kita sebut >>> print ('I am a single quoted string') I am a single quoted string >>> print ("I am a double quoted string") I am a double quoted string >>> print ("""I am a triple quoted string""") I am a triple quoted string 9, dan masukkan >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 0 di dalamnya. Sekarang kita memiliki dua variabel independen, >>> print ('I am a single quoted string') I am a single quoted string >>> print ("I am a double quoted string") I am a double quoted string >>> print ("""I am a triple quoted string""") I am a triple quoted string _9 dan >>> print ('I am a single quoted string') I am a single quoted string >>> print ("I am a double quoted string") I am a double quoted string >>> print ("""I am a triple quoted string""") I am a triple quoted string 2, yang memiliki informasi berbeda, i. e. , menetapkan nilai baru ke salah satunya tidak memengaruhi yang lain
Anda juga dapat menetapkan nilai suatu variabel menjadi nilai variabel lain. Sebagai contoh
red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10
Untuk memahami kode ini, perlu diingat bahwa nama variabel selalu berada di sebelah kiri tanda sama dengan (operator penugasan), dan nilai variabel berada di sebelah kanan tanda sama dengan. Pertama nama, lalu nilainya
Kami mulai menyatakan bahwa >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. _3 adalah >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 4, dan >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 5 adalah >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 6. Seperti yang Anda lihat, Anda dapat meneruskan beberapa argumen ke >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 7 untuk memintanya mencetak beberapa item dalam satu baris, memisahkannya dengan spasi. Seperti yang diharapkan, Python melaporkan bahwa >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. _3 menyimpan >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 4, dan >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 5 menyimpan >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 6
Sekarang kita membuat variabel ketiga, disebut >>> print ("This will result in only three backslashes: \\ \\ \\") This will result in only three backslashes: \ \ \ 2. Untuk menetapkan nilainya, kita memberi tahu Python bahwa kita ingin >>> print ("This will result in only three backslashes: \\ \\ \\") This will result in only three backslashes: \ \ \ 2 menjadi apa pun >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 3. (Ingat. nama di kiri, nilai di kanan. ) Python tahu bahwa >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. _3 adalah >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 4, jadi itu juga menetapkan >>> print ("This will result in only three backslashes: \\ \\ \\") This will result in only three backslashes: \ \ \ 2 menjadi >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 4
Sekarang kita akan mengambil variabel >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 3, dan mengaturnya ke nilai variabel >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 5. Jangan bingung — nama di sebelah kiri, nilai di sebelah kanan. Python mencari nilai >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. _5, dan menemukan bahwa itu adalah >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 6. Jadi, Python membuang nilai lama >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. _3 (>>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 4), dan menggantinya dengan >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 6. Setelah penugasan ini, Python melaporkan bahwa >>> print ("This will result in only three backslashes: \\ \\ \\") This will result in only three backslashes: \ \ \ 2 adalah >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 4, >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 3 adalah >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 6, dan >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 5 adalah >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 6
Tapi bukankah kita mengatakan bahwa >>> print ("This will result in only three backslashes: \\ \\ \\") This will result in only three backslashes: \ \ \ _2 harus bernilai berapa pun >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 3 itu? . Setelah Python mengetahui apa itu >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. _3 dan menetapkan nilai itu ke >>> print ("This will result in only three backslashes: \\ \\ \\") This will result in only three backslashes: \ \ \ 2, >>> print ("This will result in only three backslashes: \\ \\ \\") This will result in only three backslashes: \ \ \ 2 tidak lagi peduli dengan >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 3. >>> print ("This will result in only three backslashes: \\ \\ \\") This will result in only three backslashes: \ \ \ _2 memiliki nilai sekarang, dan nilai itu akan tetap sama apa pun yang terjadi pada >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 3
Catatan
Interaksi antara berbagai variabel di Python sebenarnya lebih kompleks daripada yang dijelaskan di sini. Contoh di atas berfungsi dengan bilangan bulat dan dengan semua tipe data dasar lainnya yang dibangun ke dalam Python; . Anda dapat membaca bab tentang tipe data untuk penjelasan lebih rinci tentang variabel apa yang sebenarnya ada di Python dan bagaimana tipenya memengaruhi perilakunya. Namun, mungkin cukup untuk saat ini jika Anda hanya mengingat ini. setiap kali Anda mendeklarasikan variabel atau mengubah nilainya, Anda selalu menulis nama variabel di sebelah kiri tanda sama dengan (operator penugasan), dan nilai yang ingin Anda tetapkan di sebelah kanan
Untuk nama variabel hanya boleh terdiri dari huruf besar dan huruf kecil (A-Z, a-z), angka (0-9), dan karakter garis bawah (_), dan karakter pertama nama tidak boleh angka. Misalnya, >>> print ("bouncy " * 5) bouncy bouncy bouncy bouncy bouncy >>> print ("bouncy " * 10) bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy 6 dan >>> print ("bouncy " * 5) bouncy bouncy bouncy bouncy bouncy >>> print ("bouncy " * 10) bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy 7 bukan nama variabel yang valid, sedangkan >>> print ("bouncy " * 5) bouncy bouncy bouncy bouncy bouncy >>> print ("bouncy " * 10) bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy 8 dan >>> print ("bouncy " * 5) bouncy bouncy bouncy bouncy bouncy >>> print ("bouncy " * 10) bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy 9 adalah nama variabel yang valid
'String' hanyalah daftar karakter secara berurutan. Karakter adalah segala sesuatu yang dapat Anda ketikkan pada papan ketik dengan satu penekanan tombol, seperti huruf, angka, atau garis miring terbalik. Misalnya, ">>> print (len("Hello, world!")) 13 _0" adalah sebuah string. Panjangnya lima karakter — >>> print (len("Hello, world!")) 13 _1, >>> print (len("Hello, world!")) 13 2, >>> print (len("Hello, world!")) 13 3, >>> print (len("Hello, world!")) 13 3, >>> print (len("Hello, world!")) 13 5. String juga dapat memiliki spasi. ">>> print (len("Hello, world!")) 13 _6" berisi 11 karakter. 10 huruf dan spasi antara ">>> print (len("Hello, world!")) 13 0" dan ">>> print (len("Hello, world!")) 13 8". Tidak ada batasan jumlah karakter yang dapat Anda miliki dalam sebuah string — Anda dapat memiliki mulai dari satu hingga satu juta atau lebih. Anda bahkan dapat memiliki string yang memiliki 0 karakter, yang biasanya disebut "string kosong". "
Ada tiga cara untuk mendeklarasikan string dengan Python. tanda kutip tunggal (>>> print (len("Hello, world!")) 13 9), tanda kutip ganda (question = "What did you have for lunch?" print (question) What did you have for lunch? 0), dan tanda kutip tiga (question = "What did you have for lunch?" print (question) What did you have for lunch? 1). Dalam semua kasus, Anda memulai dan mengakhiri string dengan deklarasi string pilihan Anda. Sebagai contoh
>>> print ('I am a single quoted string') I am a single quoted string >>> print ("I am a double quoted string") I am a double quoted string >>> print ("""I am a triple quoted string""") I am a triple quoted string _
Anda dapat menggunakan tanda kutip di dalam string dengan menempatkan garis miring terbalik tepat di depannya, sehingga Python mengetahui bahwa Anda ingin menyertakan tanda kutip di dalam string, alih-alih mengakhiri string di sana. Menempatkan garis miring terbalik tepat di depan simbol lain seperti ini dikenal sebagai pelolosan simbol
>>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations.
Jika Anda ingin menyertakan garis miring terbalik dalam sebuah string, Anda harus menghindari garis miring terbalik tersebut. Ini memberi tahu Python bahwa Anda ingin memasukkan garis miring terbalik ke dalam string, alih-alih menggunakannya sebagai karakter pelarian. Sebagai contoh
>>> print ("This will result in only three backslashes: \\ \\ \\") This will result in only three backslashes: \ \ \
Seperti yang Anda lihat dari contoh di atas, hanya karakter khusus yang digunakan untuk mengutip string yang perlu di-escape. Ini membuat kode lebih mudah dibaca
Untuk melihat cara menggunakan string, mari kita kembali sejenak ke program lama yang sudah dikenal
>>> print("Hello, world!") Hello, world!
Lihat itu. Anda telah menggunakan string sejak awal
Anda dapat menjumlahkan dua string menggunakan operator question = "What did you have for lunch?" print (question) What did you have for lunch? 2. ini disebut menggabungkan mereka
>>> print ("Hello, " + "world!") Hello, world!
Perhatikan bahwa ada spasi di akhir string pertama. Jika Anda tidak memasukkannya, kedua kata itu akan berjalan bersamaan, dan Anda akan berakhir dengan question = "What did you have for lunch?" print (question) What did you have for lunch? 3
Anda juga dapat mengulang string dengan menggunakan operator question = "What did you have for lunch?" print (question) What did you have for lunch? 4, seperti itu
>>> print ("bouncy " * 5) bouncy bouncy bouncy bouncy bouncy >>> print ("bouncy " * 10) bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy bouncy
String question = "What did you have for lunch?" print (question) What did you have for lunch? _5 diulangi 5 kali pada contoh pertama dan 10 kali pada contoh kedua
Jika Anda ingin mengetahui berapa panjang string, Anda menggunakan fungsi question = "What did you have for lunch?" print (question) What did you have for lunch? 6, yang hanya mengambil string dan menghitung jumlah karakter di dalamnya. (question = "What did you have for lunch?" print (question) What did you have for lunch? _7 adalah singkatan dari "panjang. ") Masukkan saja string yang ingin Anda temukan panjangnya di dalam tanda kurung fungsi. Sebagai contoh
>>> print (len("Hello, world!")) 13
Sekarang setelah Anda mempelajari tentang variabel dan string secara terpisah, mari kita lihat bagaimana keduanya bekerja sama
Variabel dapat menyimpan lebih dari sekedar angka. Anda juga dapat menggunakannya untuk menyimpan string. Begini caranya
question = "What did you have for lunch?" print (question) What did you have for lunch?
Dalam program ini, kami membuat variabel yang disebut question = "What did you have for lunch?" print (question) What did you have for lunch? 8, dan menyimpan string "question = "What did you have for lunch?" print (question) What did you have for lunch? 9" di dalamnya. Kemudian, kami hanya memberi tahu Python untuk mencetak apa pun yang ada di dalam variabel question = "What did you have for lunch?" print (question) What did you have for lunch? 8. Perhatikan bahwa ketika kita memberi tahu Python untuk mencetak ________ 73 _____8, tidak ada tanda kutip di sekitar kata ________ 73 _____8. ini memberi tahu Python bahwa kita menggunakan variabel, bukan string. Jika kita menempatkan tanda kutip di sekitar question = "What did you have for lunch?" print (question) What did you have for lunch? 8, Python akan memperlakukannya sebagai string, seperti yang ditunjukkan di bawah ini
red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 0
Mari kita coba sesuatu yang berbeda. Tentu saja, tidak apa-apa untuk bertanya kepada pengguna apa yang mereka makan untuk makan siang, tetapi tidak ada bedanya jika mereka tidak dapat menjawab. Mari edit program ini agar pengguna dapat mengetikkan apa yang mereka makan
red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _1
Untuk meminta pengguna menulis sesuatu, kami menggunakan fungsi yang disebut red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 04, yang menunggu hingga pengguna menulis sesuatu dan menekan enter, lalu mengembalikan apa yang ditulis pengguna. Jangan lupa tanda kurung. Meskipun tidak ada apa-apa di dalamnya, mereka tetap penting, dan Python akan memberi Anda kesalahan jika Anda tidak memasukkannya. Anda juga dapat menggunakan fungsi lain yang disebut red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 05, yang bekerja dengan cara yang hampir sama. Kita akan mempelajari perbedaan antara kedua fungsi ini nanti
Catatan
Dalam Python 3. x red = 5
blue = 10
print (red, blue)
5 10
yellow = red
print (yellow, red, blue)
5 5 10
red = blue
print (yellow, red, blue)
5 10 10
_04 diubah namanya menjadi red = 5
blue = 10
print (red, blue)
5 10
yellow = red
print (yellow, red, blue)
5 5 10
red = blue
print (yellow, red, blue)
5 10 10
05. Artinya, fungsi red = 5
blue = 10
print (red, blue)
5 10
yellow = red
print (yellow, red, blue)
5 5 10
red = blue
print (yellow, red, blue)
5 10 10
_05 baru membaca baris dari red = 5
blue = 10
print (red, blue)
5 10
yellow = red
print (yellow, red, blue)
5 5 10
red = blue
print (yellow, red, blue)
5 10 10
09 dan mengembalikannya tanpa baris baru yang tertinggal. Muncul red = 5
blue = 10
print (red, blue)
5 10
yellow = red
print (yellow, red, blue)
5 5 10
red = blue
print (yellow, red, blue)
5 10 10
_10 jika input dihentikan sebelum waktunya (mis. g. dengan menekan Ctrl+D). Untuk mendapatkan perilaku lama red = 5
blue = 10
print (red, blue)
5 10
yellow = red
print (yellow, red, blue)
5 5 10
red = blue
print (yellow, red, blue)
5 10 10
_05, gunakan red = 5
blue = 10
print (red, blue)
5 10
yellow = red
print (yellow, red, blue)
5 5 10
red = blue
print (yellow, red, blue)
5 10 10
12
Dalam program ini, kami membuat variabel yang disebut red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 13, dan memasukkan apa pun yang ditulis pengguna ke dalamnya. Kemudian, kami mencetak string baru, yang berisi apa pun yang ditulis pengguna. Perhatikan spasi ekstra di akhir string "red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _14", dan tanda seru di awal string "red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 15". Mereka membantu memformat output dan membuatnya terlihat bagus, sehingga string tidak berjalan bersamaan
Menggabungkan Angka dan String[sunting | sunting sumber. sunting sumber]
Lihatlah program ini, dan lihat apakah Anda dapat mengetahui apa yang seharusnya dilakukan
red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _2
Program ini harus mengambil nomor dari pengguna, menambahkan 10 ke dalamnya, dan mencetak hasilnya. Tetapi jika Anda mencoba menjalankannya, itu tidak akan berhasil. Anda akan mendapatkan error yang terlihat seperti ini
red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _3Apa yang terjadi di sini? . Secara khusus, Python tidak dapat menemukan cara merekonsiliasi dua jenis data yang digunakan secara bersamaan. bilangan bulat dan string. Misalnya, Python berpikir bahwa variabel red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _17 memegang string, bukan angka. Jika pengguna memasukkan red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 18, maka red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 17 akan berisi string dengan panjang dua karakter. a red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 20, diikuti oleh >>> print ("So I said, \"You don't know me! You'll never understand me!\"") So I said, "You don't know me! You'll never understand me!" >>> print ('So I said, "You don\'t know me! You\'ll never understand me!"') So I said, "You don't know me! You'll never understand me!" >>> print ("""The double quotation mark (\") is used to indicate direct quotations.""") The double quotation mark (") is used to indicate direct quotations. 4. Jadi bagaimana kita bisa memberi tahu Python bahwa red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _18 harus berupa angka, bukan string?
Selain itu, saat mencetak jawabannya, kami memberi tahu Python untuk menggabungkan string ("red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 23") dan angka (red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 24). Python tidak tahu bagaimana melakukan itu -- ia hanya bisa menggabungkan string menjadi satu. Bagaimana kita memberi tahu Python untuk memperlakukan angka sebagai string, sehingga kita dapat mencetaknya dengan string lain?
Untungnya, ada dua fungsi yang merupakan solusi sempurna untuk masalah ini. Fungsi red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 25 akan mengambil string dan mengubahnya menjadi integer, sedangkan fungsi red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 26 akan mengambil integer dan mengubahnya menjadi string. Dalam kedua kasus, kami menempatkan apa yang ingin kami ubah di dalam tanda kurung. Oleh karena itu, program kami yang dimodifikasi akan terlihat seperti ini
red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _4
Catatan
Cara lain untuk melakukan hal yang sama adalah menambahkan koma setelah bagian string dan kemudian variabel angka, seperti ini
red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 5
atau gunakan format cetak khusus seperti ini
red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _6
alternatif mana yang dapat ditulis dengan cara ini, jika Anda memiliki banyak masukan
red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _7
atau gunakan format()
red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _8
Itu saja yang perlu Anda ketahui tentang string dan variabel. Kita akan belajar lebih banyak tentang tipe nanti
- red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _27. Cetak informasi output ke pengguna
- red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 28 atau red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 29. meminta tanggapan pengguna, dan mengembalikan tanggapan itu. (Perhatikan bahwa dalam versi 3. x red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _29 tidak ada dan telah digantikan oleh red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 28)
- red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _32. mengembalikan panjang string (jumlah karakter)
- red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _33. mengembalikan representasi string dari suatu objek
- red = 5 blue = 10 print (red, blue) 5 10 yellow = red print (yellow, red, blue) 5 5 10 red = blue print (yellow, red, blue) 5 10 10 _34. diberi string atau angka, mengembalikan bilangan bulat
Catatan
- fungsi input dan raw_input menerima string sebagai parameter. String ini akan ditampilkan pada prompt sambil menunggu input pengguna
- Perbedaan antara keduanya adalah raw_input menerima data yang berasal dari perangkat input sebagai string mentah, sedangkan input menerima data dan mengevaluasinya menjadi kode python. Inilah sebabnya mengapa menggunakan input sebagai cara untuk mendapatkan nilai string pengguna mengembalikan kesalahan karena pengguna harus memasukkan string dengan tanda kutip
Direkomendasikan untuk menggunakan raw_input setiap saat dan menggunakan fungsi int untuk mengubah string mentah menjadi bilangan bulat. Dengan cara ini kita tidak perlu repot dengan pesan kesalahan hingga bab penanganan kesalahan dan tidak akan membuat kerentanan keamanan pada kode Anda