实验1
task1_1.py
print('hey, u')
print('hey', ' u')
x,y,z = 1,2,3
print(x, y, z)
print('x = %d, y = %d, z = %d'%(x,y,z))
print('x = {}, y = {}, z = {}'.format(x,y,z))
print(f'x = {x}, y = {y}, z = {z}')
print(x)
print(y)
print(z)
print(x, end=' ')
print(y, end=' ')
print(z)
task1_2.py
x1, y1 = 1.2,3.57
x2, y2 = 2.26, 8.7
print('{:-^40}'.format('输出1'))
print('x1 = {}, y1 = {}'.format(x1, y1))
print('x2 = {}, y2 = {}'.format(x2, y2))
print('{:-^40}'.format('输出2'))
print('x1 = {:.1f}, y1 = {:.1f}'.format(x1, y1))
print('x2 = {:.1f}, y2 = {:.1f}'.format(x2, y2))
print('{:-^40}'.format('输出3'))
print('x1 = {:<15.1f}, y1 = {:<15.1f}'.format(x1, y1))
print('x2 = {:<15.1f}, y2 = {:<15.1f}'.format(x2, y2))
print('{:-^40}'.format('输出3'))
print('x1 = {:>15.1f}, y1 = {:>15.1f}'.format(x1, y1))
print('x2 = {:>15.1f}, y2 = {:>15.1f}'.format(x2, y2))
task1_3.py
name1, age1 = 'Bill', 19 name2, age2 = 'Hellen', 18 title = 'Personnel Information' print(f'{title:=^40}') print(f'name: {name1:10}, age: {age1:3}') print(f'name: {name2:10}, age: {age2:3}') print(40*'=')
总结:一般情况下,print()函数只需要一个参数就可以输出一个对象了,而且这个对象可以是任意类型,包括列表、数字、字符串等。print()函数可以有多个参数,这些参数会首先全转换为字符串,然后用空格拼接起来,变成一个完整的字符串输出。print()函数可以分行或者合并成一行输出。print()函数还可以格式化输出。
task2_1.py
r1 = eval('1 + 2') print(type(r1), r1)
r2 = eval('[1, 6, 7.5]') print(type(r2), r2)
r3 = eval('"python"') print(type(r3), r3)
r4 = eval('7, 42') print(type(r4), r4)
task2_2.py
x, y = eval(input('Enter two oprands: ')) ans = x + y print(f'{x} + {y} = {ans}') print(f'{type(x)} + {type(y)} = {type(ans)}')
总结:eval()函数用于执行一个字符串表达式,并返回表达式的值。
task3.py
ans1 = 0.1 + 0.2 print(f'0.1 + 0.2 = {ans1}') from decimal import Decimal ans2 = Decimal('0.1') + Decimal('0.2') print(f'0.1 + 0.2 = {ans2}')
1.它转化成二进制有误差
2.decimal()可以进行十进制浮点运算。decimal传入的浮点数要加引号,表示成字符串形式。
可以传递给decimal整形或者字符串参数。从浮点数据转换为decimal类型。通过设定有效数字,限定结果样式。四舍五入,保留几位小数,decimal结果转化为string。
task4.pyprint(chr(0x1f600), end = " ")
print(chr(0x1f600), end = " ")
print(chr(0x1f601), end = " ")
print(chr(0x1f602), end = " ")
print(chr(0x1f603), end = " ")
print(chr(0x1f604))
print(chr(10000), end=" ")
print(chr(0x025b), end=" ")
print(chr(0x2708), end=" ")
print(chr(0x00A5), end=" ")
print(chr(0x266b))
print(ord('a'), end = " ")
print(ord('b'), end = " ")
print(ord('c'))
print(ord('A'), end = " ")
print(ord('B'), end = " ")
print(ord('C'))
print(ord('0'), end = " ")
print(ord('1'), end = " ")
print(ord('2'))
总结:
1.chr()函数可以将一个整数转换为一个字符
2.ord()函数可以将一个字符转换为它的整数值
task5_1.py
from math import sqrt n = float(input('输入一个数:')) ans1 = sqrt(n) ans2 = n**0.5 print('%.2f的平方根是: %.2f' %(n, ans1)) print('{:.2f}的平方根是: {:.2f}'.format(n, ans2)) print(f'{n:.2f}的平方根是: {ans2:.2f}'
task6.py
task7.py
实验总结:
1.通过本次实验,我对print()用于输出的几种常用用法更加熟悉,理解了eval(),chr(),ord()的用法。
2.新学会了decimal(),并了解了它的功能。但是使用起来还不是很熟练。
3.当需要输出很多内容时,用print(f' ')会比逐行用print()方便。