Simple example:
5*(3+4)-6
when entered in the text box, evaluates to 29
Javascript routines, as well as expressions, can be evaluated.
For example, the following code:
a = 0
for (i=0; i<10; i++) {
a = a + i
}
return a
when entered in the text box, evaluates to 45
Math functions must be preceded by "Math."
JavaScript supports the following math functions:
Math.abs(a) // the absolute value of a
Math.acos(a) // arc cosine of a
Math.asin(a) // arc sine of a
Math.atan(a) // arc tangent of a
Math.atan2(a,b) // arc tangent of a/b
Math.ceil(a) // integer closest to a and not less than a
Math.cos(a) // cosine of a
Math.exp(a) // the constant e raised to power a
Math.floor(a) // integer closest to and not greater than a
Math.log(a) // log of a base e
Math.max(a,b) // the maximum of a and b
Math.min(a,b) // the minimum of a and b
Math.pow(a,b) // a to the power b
Math.random() // pseudorandom number in the range 0 to 1
Math.round(a) // integer closest to a
Math.sin(a) // sine of a
Math.sqrt(a) // square root of a
Math.tan(a) // tangent of a
Math constants are:
Math.E // base of the natural log system
Math.LN10 // natural log of 10
Math.LN2 // natural log of 2
Math.PI // pi
Math.SQRT1_2 // square root of 1/2
Math.SQRT2 // square root of 2
Example:
Math.sin(Math.PI/2)
Evaluates to 1
Here are a few string functions, where "str" = name of your string:
str.length // returns length of str
str.charAt(x) // returns the character at position x
str.indexOf(x,y) // returns the first occurrence of character x starting from position y
str.lastIndexOf(x,y) // returns the last occurrence of character x starting from position y
str.substring(x,y) // returns a portion of a string, from character x to character y
str.toLowerString() // converts a string to lowercase
str.toUpperString() // converts a string to uppercase
Example:
s = "applebanana"
len = s.length
sub = s.substring(3,10)
gives results len = 11, sub = "lebanan"
Here is an example of a routine to invert a string
str = "applebanana"
len = str.length
strout = ""
for (var i=len-1; i>=0; i--) {
strout=strout + str.charAt(i)
}
return strout