SECTION 68 in Java

Drawer DataMatrix in Java SECTION 68
SECTION 68
Data Matrix Generation In Java
Using Barcode drawer for Java Control to generate, create ECC200 image in Java applications.
TESTING THE MARKOV PROGRAM
Bar Code Encoder In Java
Using Barcode encoder for Java Control to generate, create barcode image in Java applications.
A second test verified conservation properties For two-word prefixes, every word, every pair, and every triple that appears in the output of a run must occur in the input as well We wrote an Awk program that reads the original input into a giant array builds arrays of all pairs and triples, then reads the Markov output into another array and compares the two:
Scanning Bar Code In Java
Using Barcode recognizer for Java Control to read, scan read, scan image in Java applications.
# markov t e s t : check t h a t a l l words, p a i r s , t r i p l e s i n # output ARGV[2] are i n o r i g i n a l i n p u t ARGV[l] BEGIN {
Making ECC200 In Visual C#
Using Barcode creation for VS .NET Control to generate, create Data Matrix ECC200 image in Visual Studio .NET applications.
while (get1 i iARGV[l] > 0) ne = ; { f o r (i 1 i <= NF; i++) wd[++nw] = B i # i n p u t words singleC$il++ T f o r (i= 1 i <nw; i++) ; p a i r [ w d [ i l ,wd[i+lll++ f o r ( = 1 i < nw-1; i++) i ; t r i p l e [ w d [ i ] wd[i+l] ,wd[i+21]++ while ( g e t l i n e <ARCV[2] > 0) { outwd[++ow] = $0 # output words i f (!(SO i n single)) p r i n t "unexpected word" $0 f o r (i= 1 i < ow; i++) ; i f (! ((outwd[il , outwd[i+l]) i n pai r)) p r i n t "unexpected pai r" , outwd[i] , outwd[i+ll f o r (i 1 i < ow-1; i++) = ; i f (!((outwd[i],outwd[i+1],outwd[i+2]) i n triple)) p r i n t "unexpected t r i p l e " , outwd[i] , outwd[i+l] , outwd[i+21
Make DataMatrix In .NET Framework
Using Barcode generator for ASP.NET Control to generate, create ECC200 image in ASP.NET applications.
We made no attempt to build an efficient test, just to make the test program as simple as possible It takes six or seven seconds to check a 10,000 word output file against a 42,685 word input file, not much longer than some versions of Markov take to generate it Checking conservation caught a major error in our Java implementation: the program sometimes overwrote hash table entries because it used references instead of making copies of prefixes This test illustrates the principle that it can be much easier to verify a property of the output than to create the output itself For instance it is easier to check that a file is sorted than to sort it in the first place A third test is statistical in nature The input consists of the sequence
Generating DataMatrix In .NET
Using Barcode generator for VS .NET Control to generate, create ECC200 image in .NET applications.
a b c a b c
ECC200 Generation In Visual Basic .NET
Using Barcode creation for VS .NET Control to generate, create Data Matrix ECC200 image in .NET framework applications.
a b d
Printing Barcode In Java
Using Barcode generation for Java Control to generate, create bar code image in Java applications.
with ten occurrences of abc for each abd The output should have about 10 times as many c's as d's if the random selection is working properly We confirm this with f req, of course
EAN-13 Supplement 5 Generator In Java
Using Barcode generation for Java Control to generate, create EAN13 image in Java applications.
The statistical test showed that an early version of the Java program, which associated counters with each suffix, produced 20 c's for every d, twice as many as it should have After some head scratching, we realized that Java's random number generator returns negative as well as positive integers; the factor of two occurred because the range of values was twice as large as expected so twice as many values would be zero modulo the counter; this favored the first element in the list, which happened to be c The fix was to take the absolute value before the modulus Without this test, we would never have discovered the error; to the eye, the output looked fine Finally, we gave the Markov program plain English text to see that it produced beautiful nonsense Of course, we also ran this test early in the development of the program But we didn't stop testing when the program handled regular input because nasty cases will come up in practice Getting the easy cases right is seductive; hard cases must be tested too Automated, systematic testing is the best way to avoid this trap All of the testing was mechanized A shell script generated necessary input data, ran and timed the tests, and printed any anomalous output The script was configurable so the same tests could be applied to any version of Markov, and every time we made a set of changes to one of the programs, we ran all the tests again to make sure that nothing was broken
Paint Barcode In Java
Using Barcode printer for Java Control to generate, create barcode image in Java applications.
69 Summary
Making Barcode In Java
Using Barcode maker for Java Control to generate, create barcode image in Java applications.
The better you write your code originally, the fewer bugs it will have and the more confident you can be that your testing has been thorough Testing boundary conditions as you write is an effective way to eliminate a lot of silly little bugs Systematic testing tries to probe at potential trouble spots in an orderly way; again failures are most commonly found at boundaries which can be explored by hand or by program As much as possible, it is desirable to automate testing, since machines don't make mistakes or get tired or fool themselves into thinking that something is working when it isn't Regression tests check that the program still produces the same answers as it used to Testing after each small change is a good technique for localizing the source of any problem because new bugs are most likely to occur in new code The single most important rule of testing is to do it
Creating DataMatrix In Java
Using Barcode generation for Java Control to generate, create Data Matrix 2d barcode image in Java applications.
Paint MSI Plessey In Java
Using Barcode printer for Java Control to generate, create MSI Plessey image in Java applications.
Print Code 39 Full ASCII In .NET
Using Barcode generator for VS .NET Control to generate, create USS Code 39 image in Visual Studio .NET applications.
UPCA Recognizer In .NET Framework
Using Barcode recognizer for .NET Control to read, scan read, scan image in Visual Studio .NET applications.
Generating Data Matrix ECC200 In .NET Framework
Using Barcode maker for .NET framework Control to generate, create Data Matrix image in .NET framework applications.