I won't say much nonsense, everyone should just look at the code!
a1 =raw_input("please input a number")
a =int(a1)if(a!=0):if(a 0):
print 'This is a positive number'if(a <0):
print 'This is negative'else:
print 'the number is equal to 0'
Supplementary knowledge: Determine whether a value is positive, negative, zero, or integer
When I was reading "Introduction to ES6 Standards" by Teacher Ruan Yifeng recently, I saw that ES6 has added two new methods.
Used to judge a value.
1. Judging the integer-Number.isInteger()
Number.isInteger() First judge whether the value is of type number, instead of returning false directly;
If it is a number type, it is judged whether it is an integer.
Number.isInteger(25);//true
Number.isInteger(25.222);//false
Number.isInteger('25');// false
Number.isInteger('25.222');//false
Number.isInteger('foo');// false
It is also very simple to use Es5 to judge whether it is a positive number. There are many ways to implement it. Here are two:
1、 Use Math.round, use rounding to determine whether the value is an integer.
functionnumberIsInteger(n){if(!Number.isInteger){returntypeof n ==='number'&& Math.round(n)=== n;}return n;}
2、 Use the remainder.
functionnumberIsInteger(n){if(!Number.isInteger){returntypeof n ==='number'&& n %1===0;}return Number.isInteger(n);}
Second, determine whether a number is positive, negative, or zero---Math.sign()
Return 5 values:
+1 A positive number
- 1 negative number
0 0- 0 -0
NaN other values
console.log(Math.sign(-5));//-1
console.log(Math.sign(-5.222));// -1
console.log(Math.sign(555));// 1
console.log(Math.sign(0));// 0
console.log(Math.sign(-0));// -0
console.log(Math.sign('foo'));// NaN
Es5 implementation method:
Math.sign = Math.sign ||function(n){
n =+n;if(n ===0||isNaN(n)){return n;}return x 0?1:-1;}
The above python method of judging positive and negative numbers is all the content shared by the editor, I hope to give you a reference.
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