Debugging Techniques in .NET framework Creating PDF417 in .NET framework Debugging Techniques

How to generate, print barcode using .NET, Java sdk library control with example project source code free download:
Debugging Techniques use .net framework qr code jis x 0510 implement toattach qr with .net MSI Plessey r plotting Visual Studio .NET QR Code the wrong kind of object, and r using uppercase instead of lowercase letters in MATLAB commands, or. misspelling commands. Debugging Techniques Now that w e have discussed the most common mistakes, it s time to discuss how to debug your M- les, and how to locate and x those pesky problems that don t t into the neat categories above. If one of your M- les is not working the way you expected, perhaps the easiest thing you can do to debug it is to insert the command keyboard somewhere in the middle. This temporarily suspends (but does not stop) execution and returns command to the keyboard, where you are given a special prompt with a K in it.

You can execute whatever commands you want at this point (for instance, to examine some of the variables). To return to execution of the M- le, type return or dbcont, short for debug continue. A more systematic way to debug M- les is to use the MATLAB M- le debugger to insert breakpoints in the le.

Usually you would do this with the Breakpoints menu or with the Set/clear breakpoint icon at the top of the Editor/Debugger window, but you can also do this from the command line with the command dbstop. Once a breakpoint is inserted in the M- le, you will see a little red dot next to the appropriate line in the Editor/Debugger. (An example is illustrated in Figure 11-8 below.

) Then when you call the M- le, execution will stop at the breakpoint, and just as in the case of keyboard, control will return to the Command Window, where you will be given a special prompt with a K in it. Again, when you are ready to resume execution of the M- le, type dbcont. When you are done with the debugging process, dbclear clears the breakpoint from the M- le.

Let s illustrate these techniques with a real example. Suppose you want to construct a function M- le that takes as input two expressions f and g (given either as symbolic expressions or as strings) and two numbers a and b, plots the functions f and g between x = a and x = b, and shades the region in between them. As a rst try, you might start with the nine-line function M- le shadecurves.

m given as follows:. function s QR Code for .NET hadecurves(f, g, a, b) %SHADECURVES Draws the region between two curves % SHADECURVES(f, g, a, b) takes strings or expressions f % and g, interprets them as functions, plots them between % x = a and x = b, and shades the region in between..

11: Troubleshooting Figure 11-3. % Example: shadecurves( sin(x) , -sin(x) , 0, pi) ffun = inline(vectorize(f)); gfun = inline(vectorize(g)); xvals = a:(b - a)/50:b; plot([xvals, xvals], [ffun(xvals), gfun(xvals)]). Trying this M- le out with the example speci ed in the help lines, that is, executing >> s hadecurves( sin(x) , -sin(x) , 0, pi). >> s Visual Studio .NET QR Code yms x; shadecurves(sin(x), -sin(x), 0, pi). gives the output shown in Figure 11-3. This is not really what we wanted; the gure we seek is shown in Figure 11-4. To begin to determine what went wrong, let s try a different example, say.

>> shadecurves( x 2 , sqrt(x) , 0, 1) >> axis square >> syms x; shadecurves(x 2, sqrt(x), 0, 1) >> axis square Now we get qr barcode for .NET the output shown in Figure 11-5..

Debugging Techniques Figure 11-4. Figure 11-5. 11: Troubleshooting It s not t oo hard to gure out why our regions aren t shaded; that s because we used plot (which plots curves) instead of patch (which plots lled patches). So that suggests we should try changing the last line of the M- le to. patch([xva Quick Response Code for .NET ls, xvals], [ffun(xvals), gfun(xvals)]). That gives the error message Error Visual Studio .NET QR Code ISO/IEC18004 using ==> patch Not enough input arguments. Error in ==> shadecurves.

m On line 9 ==> patch([xvals, xvals], [ffun(xvals), gfun(xvals)]). So we go back and try >> help patch to see if we can get the syntax right. The help lines indicate that patch requires a third argument, the color (in RGB coordinates) with which our patch is to be lled. So we change our nal line to, for instance,.

patch([xva Denso QR Bar Code for .NET ls,xvals], [ffun(xvals),gfun(xvals)], [.2,0,.

8]). That gives us now as output to shadecurves(x 2, sqrt(x), 0, 1); axis square the picture shown in Figure 11-6. That s better, but still not quite right, because we can see a mysterious diagonal line down the middle. Not only that, but if we try.

>> s .net framework QR Code 2d barcode yms x; shadecurves(x 2, x 4, -1.5, 1.

5). we now get the bizarre picture shown in Figure 11-7. There aren t a lot of lines in the M- le, and lines 7 and 8 seem OK, so the problem must be with the last line. We need to reread the online help for patch.

It indicates that patch draws a lled 2D polygon de ned by the vectors X and Y, which are its rst two inputs. A way to see how this is working is to change the 50 in line 9 of the M- le to something much smaller, say 5, and then insert a breakpoint in the M- le before line 9. At this point, our M- le in the Editor/Debugger window now looks like Figure 11-8.

Note the large dot to the left of the last line, indicating the breakpoint. When we run the M- le with the same input, we now obtain in the Command Window a K>> prompt. At this point, it is logical to try to list the coordinates of the points that are the vertices of our lled polygon, so we try.

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