![]() ![]() any calculation which includes NaN as one of its operands.logarithm (any base) of a non-positive number.A few examples of calculations which produce NaN are: LabVIEW implements the IEEE-754 standard for floating-point calculations, which specifies unique values for the outputs of mathematical operations which have no meaningful numerical result. Size of binary SGL file is n*4, where n is number of data samples.Įxample: FileFormatsBench.vi Download FileFormatsBench.NaN is the notation in LabVIEW for the floating-point value Not-a-Number. Size of binary I16 file is n*2, where n is number of data samples.Įach datum consists of 4 bytes. However, data acquisition parameters like scale offset, scale multiplier, and polarity can be saved in simple header in the same file. Only unscaled (integer) data can be written in this way. For Windows, the value is CRLF for Macintosh, the value is CR and for UNIX, the value is LF.Ī simplest byte stream file is an array of binary 16-bit integers or 32-bit single-precision, floating point numbers, which you acquire from a data acquisition (DAQ) program.Įach datum consists of 2 bytes. If you need to append one, use the End-of-Line constant from the String palette.Ĭonsists of a constant string containing the platform-dependent, end of line value. \xx character with hexadecimal ASCII code xx (using 0 through 9 and upper case A through F)Ī code does not exist for the platform-dependent end-of-line (eol) character. (5*8 4 tabs 2 bytes of EOL = 46 bytes) The size of this file will be, correspondingly, will be 31 bytes: 5*5 4 tabs 2 bytes of EOL (CR LF, see table below). For example, if conversion format is %.3f, then the file data.dat, containing array of 5 samples (see FileFormatBench.vi) will look like: The number of characters per numeric value depends on conversion format. You can use this VI to create a text file readable by most spreadsheet applications.Įach character in ASCII text file (including control characters) takes one byte. This VI opens or creates the file before writing to it and closes it afterwards. This function writes the string to a file or appends the string to an existing file. This function takes care of the conversion of numbers to spreadsheet string (it calls the Array to Spreadsheet String function to convert a 2D or 1D array of single-precision (SGL) numbers to a text string). The numbers are converted according to supplied format string, for example %.3f (default format).Īfter conversion, the spreadsheet string can be written to a file with functionĪlternatively, numeric data can be written to file with function Spreadsheet string is a table in string form, containing tabs (or other specified delimiters) separating column elements, a platform-dependent EOL (see below) character separating rows, and, for arrays of three or more dimensions, separated pages. This function converts an array of any dimension to spreadsheet string. Note that converting large amounts of data to and from strings can be time consuming. In order to save the numeric data to ASCII text file, we should convert the numeric values to strings. LabVIEW can save numeric data to ASCII (text) files or byte stream (binary) files: ![]()
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