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# Calculator Index

Except for the last one, the above are modules that perform a variety of trigonometric functions, designed especially for use by students and machinists in machine shops who do not have the luxury of a CAD/CAM system or a sophisticated control to program their CNC machinery or to get numbers for manual machining.

## General Information

### Angles:

The standard convention is used for these modules, with zero degrees being along the positive X axis, which is to the right in the three o'clock direction on your screen. The angle increases in size as it moves counterclockwise toward the positive Y axis, which is straight up in the 12 o'clock direction on your screen. The 12 o'clock position is at 90° degrees, the nine o'clock position, the negative X axis, is at 180°, and the six o'clock position is at 270°. The 270° position could also be referred to as -90°.

### Math entries:

The data that you input into the boxes may also contain math operations, which are +, -, *, / (addition, subtraction, multiplication, and division) The module will perform multiplication and division before it does any addition or subtraction, so 3 + 4 * 5 will be equal to 23. If you want a different order, operations enclosed in parenthesis will be performed first, so (3 + 4) * 5 will be equal to 35.

## Triangle Solutions

With this module, you only need to fill in two boxes with information, and the rest will be calculated for you. One of the boxes must be a length of a side, and the other may be either a side or an angle. If you enter a side and an angle, notice that one box is for if the angle is next (adjacent) to the side that you gave, and the other box is if the angle is opposite the given side. The solution will be different in each case, so be sure to enter the information in the proper box. If you give the hypotenuse (the longest side, the one opposite the 90° angle) as the known side, it doesn't matter which box you put the angle in, although of course technically it is adjacent to the given side.

## Bolt Circle Solutions

A bolt circle (a pattern of holes) may be calculated for an entire circle, or just a section of the circle. For the diameter of the circle, if you are only given a radius on the print, you may use the module itself as your calculator and simply enter the radius given followed by *2 (the asterisk is what is used as the times key on a computer). If no starting angle is given, the module assumes that zero degrees (three o'clock direction) should be used. If no ending angle is given, it is assumed that the pattern should span an entire 360 degrees.

## Linear Pattern Solutions

A linear pattern may be defined in one of two ways. It is given a starting point (or assumes a start of [0,0] if the boxes are left empty), and then either an angle and an increment, or the location of the final hole. Finally, the number of holes in the pattern should be filled in. If this is left empty, then a pattern of two holes will be assumed. This is to make it easy to determine the distance between two points and the angle by just entering the coordinates for the starting and ending hole, clicking the button to solve the pattern, and reading the angle and increment that the module calculates. In the future, the script will be modified so that an angle and either a final X or Y coordinate may be given to let the module calculate the increment and unknown coordinate.

## Line-Line Intercept Solutions

This module will find the intersection point of two lines. The lines can not be parallel, since then they would never intersect. To define the lines, give the coordinates of one point on the line, and the angle of the line. An angle of 30°, 210°, and -150° all refer to the same line.

## Circle-Line Intercept Solutions

This module will give the intersecting points of a line and a circle. If the X & Y coordinates on both the line and the circle are left blank, and only the diameter and angle of the line are given, it will give an answer similar to that obtained from the triangle solver, if the diameter is entered as twice what the hypotenuse was entered as, and the same angle is entered. (The coordinate for the intersection is the same as the two unknown sides of the triangle.)

## Circle-Circle Intercept Solutions

This module is used to find the intersection points of two circles. It can also be used to find a point that is a specified distance from one known point, and either the same or a different distance from another point. By making the center of the circle to be the known point, and the diameter twice that of the desired distance from the known point, and doing the same for the other known point, where the two circles intersect is the location that needs to be found.

## 3 Points on a Circle Solutions

This module is used to find the center of a circle and the diameter of a circle that pass through three points. The only requirement is that the three points do not lie in a line.