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asp.net barcode reader free x = r cos q and y = r sin q in .NET
x = r cos q and y = r sin q Code 3/9 Recognizer In .NET Using Barcode Control SDK for VS .NET Control to generate, create, read, scan barcode image in VS .NET applications. Code39 Generation In VS .NET Using Barcode creator for .NET Control to generate, create ANSI/AIM Code 39 image in .NET framework applications. p /2 Read Code39 In .NET Framework Using Barcode scanner for .NET Control to read, scan read, scan image in .NET framework applications. Encoding Bar Code In .NET Framework Using Barcode creator for .NET Control to generate, create bar code image in .NET applications. 3p /2 Decoding Bar Code In .NET Framework Using Barcode reader for .NET Control to read, scan read, scan image in .NET applications. Code 39 Printer In Visual C#.NET Using Barcode generator for VS .NET Control to generate, create Code39 image in Visual Studio .NET applications. Figure 36 A point plotted in both polar and Cartesian
Code39 Encoder In .NET Using Barcode drawer for ASP.NET Control to generate, create USS Code 39 image in ASP.NET applications. Code 3/9 Printer In VB.NET Using Barcode creator for VS .NET Control to generate, create Code 3 of 9 image in .NET framework applications. coordinates Each radial division in the polar grid represents 1 unit Each division on the x and y axes of the Cartesian grid also represents 1 unit The shaded region is a right triangle x units wide, y units tall, and having a hypotenuse r units long Printing Barcode In Visual Studio .NET Using Barcode encoder for Visual Studio .NET Control to generate, create barcode image in VS .NET applications. DataMatrix Generation In VS .NET Using Barcode printer for .NET framework Control to generate, create ECC200 image in .NET framework applications. Polar TwoSpace
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Create GTIN  128 In ObjectiveC Using Barcode generator for iPhone Control to generate, create GS1128 image in iPhone applications. USS Code 39 Decoder In None Using Barcode reader for Software Control to read, scan read, scan image in Software applications. Cartesian to polar: the radius Figure 36 shows us that the radius r from the origin to our point P = (x,y) is the length of the hypotenuse of a right triangle (the shaded region) that s x units wide and y units tall Using the Pythagorean theorem, we can write the formula for determining r in terms of x and y as r = (x 2 + y 2 )1/2 That s straightforward enough Now it s time to work on the more difficult conversion: finding the polar angle for a point that s given to us in the Cartesian xy plane The Arctangent function Before we can find the polar direction angle for a point that s given to us in Cartesian coordinates, we must be familiar with an inverse trigonometric function known as the Arctangent, which undoes the work of the tangent function (The capital A is not a typo We ll see why in a minute) Consider, for example, the fact that tan (p /4) = 1 A true function that undoes the tangent must map an input value of 1 in the domain to an output value of p /4 in the range, but to no other values In fact, no matter what we input to the function, we must never get more than one output To ensure that the inverse of the tangent behaves as a true function, we must restrict its range (output) to an open interval where we don t get any redundancy By convention, mathematicians specify the open interval ( p /2,p /2) for this purpose When mathematicians make this sort of restriction in an inverse trigonometric function, they capitalize the first letter in the name of the function That s a code to tell us that we re working with a true function, and not a mere relation Some texts use the abbreviation tan 1 instead of Arctan to represent the inverse of the tangent function We won t use this symbol here because some readers might confuse it with the reciprocal of the tangent, which is the cotangent, not the Arctangent! If you re curious as to what the Arctangent function looks like when graphed, check out Fig 37 This graph consists of the principal branch of the tangent function, tipped on its side and then flipped upsidedown Compare Fig 37 with Fig 25 on page 28 The principal branch of the tangent function is the one that passes through the origin Once we ve made sure we won t run into any ambiguity, we can state the above fact using the Arctangent function, getting Arctan 1 = p /4 For any real number u except oddinteger multiples of p /2 (for which the tangent function is undefined), we can always be sure that Arctan (tan u) = u Going the other way, for any real number v, we can be confident that tan (Arctan v) = v

