For basic mathematical operations, you can use the following signs: + (addition), - (subtraction), * (multiplication) and / (division).

Just as usual, you can place parts of equation into brackets if you want certain actions to be done first, e.g. (a+b)*(c/d) etc.

For other mathematical operations, please use the following functions:

pi	Returns an approximation of pi.
round(x,precision)	Returns the rounded value of x to specified precision (number of digits after the decimal point). Precision is 0 by default and can be omitted, e.g. round(24.35)=24
sqrt(x)	Returns square root of x.
abs(x)	Returns the absolute value of number (always positive).
ratio(x/y)	Returns the integer after division, e.g. ratio(11/4) will return 2.
cmtoin(x)	Helps to convert a value in centimeters into inches. Returns a float rounded to the first decimal, e.g. cmtoin(20) will return 7.9.
intocm(x)	Helps to convert a value in inches into centimeters. Returns a float rounded to the first decimal, e.g. intocm(8) will return 20.3.
sin(x)	Returns sine of x (in degrees).
cos(x)	Returns cosine of x (in degrees).
tan(x)	Returns tangent of x (in degrees).
asin(x)	Returns arcsine (in degrees) of x (in degrees).
acos(x)	Returns arccosine (in degrees) of x.
atan(x)	Returns arctangent (in degrees) of x.

Frequently used formulas

Here are some formulas you might require when making sewing patterns:

Length of a circle = 2*pi*radius

Trigonometric functions for a triangle with straight angle

sin(a)=AB/OB
cos(a)=OA/OB
tan(a)=AB/OA

Or, if you need to find lengths using angles and length of one of the sides, then:

OB=AB/sin(a)=OA/cos(a)
AB=OB*sin(a)=OA*tan(a)
OA=OB*cos(a)=AB/tan(a)