mzcdfread

从NETCDF文件中读取质谱数据

Syntax

mzCDFStruct= mzcdfread(文件) mzCDFStruct= mzcdfread(文件， ...'时间范围'，TimeRangeValue,……) mzCDFStruct= mzcdfread(文件,……”ScanIndices',ScanindicesValue,……) mzCDFStruct= mzcdfread(文件，...'冗长'，VerboseValue,……)

Input Arguments

`文件`	Character vector or string containing a file name, or a path and file name, of a netCDF file that contains mass spectrometry data and conforms to the ANDI/MS or the ASTM E2077-00 (2005) standard specification or earlier specifications. If you specify only a file name, that file must be on the MATLAB^®search path or in the current folder.
`TimeRangeValue`	两元素数字阵列`[Start End]`that specifies the time range in`文件`for which to read spectra. Default is to read spectra from all times`[0 Inf]`。 Tip 时间单元在NETCDF全局属性中指示。有关NetCDF文件中时间范围的摘要信息，请使用`mzcdfinfo`function. Note If you specify a`TimeRangeValue`, you cannot specify a`ScanindicesValue`。
`ScanindicesValue`	Positive integer, vector of integers, or a two-element numeric array`[start_ind end_ind]`指定扫描，多次扫描或一系列扫描`文件`读书。`Start_Ind`和`End_Ind`are each positive integers indicating a scan index number.`Start_Ind`must be less than`End_Ind`。默认是阅读所有扫描。 Tip 有关NetCDF文件中扫描索引的信息，请检查`NumberOfScans`field in the structure returned by the`mzcdfinfo`function. Note If you specify a`ScanindicesValue`, you cannot specify`TimeRangeValue`。
`VerboseValue`	Controls the display of the progress of the reading of`文件`。Choices are`真的`(default) or`false`。

Output Arguments

mzCDFStruct

MATLAB结构包含来自NetCDF文件的质谱信息。它的字段对应于NetCDF文件中的变量和全局属性。如果NETCDF变量包含本地属性，则创建了一个附加字段，该字段的名称是附加的变量名称_属性。The number and names of the fields will vary, depending on the mass spectrometer software, but typically there aremass_values和intense_valuesfields.

Description

mzCDFStruct= mzcdfread(文件)读取NetCDF文件，文件, and then creates a MATLAB structure,mzCDFStruct。

文件is a character vector or string containing a file name, or a path and file name, of a netCDF file that contains mass spectrometry data. The file must conform to the ANDI/MS or the ASTM E2077-00 (2005) standard specification or earlier specifications.

mzCDFStructcontains fields that correspond to the variables and global attributes in a netCDF file. If a netCDF variable contains local attributes, an additional field is created, with the name of the field being the variable name appended with_属性。The number and names of the fields will vary, depending on the mass spectrometer software, but typically there aremass_values和intense_valuesfields.

Tip

LC/MS数据分析需要操作系统的大量内存。

如果收到与内存有关的错误，请尝试以下内容：
- Increase the virtual memory (swap space) for your operating system as described inResolve “Out of Memory” Errors。
If you receive errors related to Java^®堆空间，增加爪哇堆空间：
- If you have MATLAB version 7.10 (R2010a) or later, seeJava Heap内存首选项。
- If you have MATLAB version 7.9 (R2009b) or earlier, see//www.tatmou.com/support/solutions/en/data/1-18I2C/。

mzCDFStruct= mzcdfread(文件,……”PropertyName',PropertyValue,……)callsmzcdfreadwith optional properties that use property name/property value pairs. You can specify one or more properties in any order. EachPropertyNamemust be enclosed in single quotation marks and is case insensitive. These property name/property value pairs are as follows:

mzCDFStruct= mzcdfread(文件， ...'时间范围'，TimeRangeValue,……)specifies the range of time in文件读书。TimeRangeValue是两个元素数字阵列[Start End]。Default is to read spectra from all times[0 Inf]。

Tip

时间单元在NETCDF全局属性中指示。有关NetCDF文件中时间范围的摘要信息，请使用mzcdfinfofunction.

Note

If you specify aTimeRangeValue, you cannot specifyScanindicesValue。

mzCDFStruct= mzcdfread(文件,……”ScanIndices',ScanindicesValue,……)指定扫描，多次扫描或扫描范围文件读书。ScanindicesValueis a positive integer, vector of integers, or a two-element numeric array[start_ind end_ind]。Start_Ind和End_Indare each positive integers indicating a scan index number.Start_Indmust be less thanEnd_Ind。默认是阅读所有扫描。

Tip

有关NetCDF文件中扫描索引的信息，请检查NumberOfScansfield in the structure returned by themzcdfinfofunction.

Note

If you specify aScanindicesValue, you cannot specify aTimeRangeValue。

mzCDFStruct= mzcdfread(文件，...'冗长'，VerboseValue,……)controls the progress display when reading文件。Choices are真的(default) orfalse。

Examples

在下面的示例中，文件results.cdf未提供。

将NETCDF文件读取到MATLAB软件中作为结构。
```
out = mzcdfread('results.cdf');
```

View the second scan in the netCDF file by creating separate variables containing the intensity and m/z values, and then plotting these values. Add a title andx- 和y-axis labels using fields in the output structure.

idx1 = out.scan_index(2)+1; idx2 = out.scan_index(3); y = out.intensity_values(idx1:idx2); z = out.mass_values(idx1:idx2); stem(z,y,'marker','none') title(sprintf('Time: %f',out.scan_acquisition_time(2))) xlabel(out.mass_axis_units) ylabel(out.intensity_axis_units)