TI-BASIC:R Pr

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RTOPR.GIF

Command Summary

R►Pr( calculates the radius component (in polar coordinates) given the Cartesian coordinates.

Command Syntax

R►Pr(x,y)

Menu Location

Press:

  1. 2nd ANGLE to access the angle menu.
  2. 5 to select R►Pr(, or use arrows and ENTER.

Calculator Compatibility

TI-83/84/+/SE

Token Size

1 byte

R►Pr( (Rectangular to polar radius) takes the (x,y) (Cartesian) coordinates, and gives the radius coordinate r of the same point in (r,θ) (polar) mode. The identity used for this conversion is r² = x²+y²

R►Pr(3,4)
	5
√(3²+4²)
	5
R►Pr({6,5},{8,12})
	{10 13}

The function works even when the equivalent √(x²+y²) fails due to overflow:

R►Pr(3e99,4e99)
	5e99

Optimization

R►Pr( is the smallest way to implement the distance formula <math>d=\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}</math>. Just pass it the values x,,1,,-x,,2,, and y,,1,, - y,,2,, as arguments:

:√((5-2)²+(4-0)²)
can be
:R►Pr(5-2,4-0)

Error Conditions

Related Commands