Why does the Signal Processing Toolbox 6.1 (R13SP1) cause MATLAB to crash when I use BUFFER with an input that is a cell array?

Why does the Signal Processing Toolbox 6.1 (R13SP1) cause MATLAB to crash when I use BUFFER with an input that is a cell array?

When I run the code:

x = {{4};{3}};

t = buffer(x,8);

clear x

I get variables created whose values are my crash dump.Also, if I run the following code,

x = {7};

t = buffer(x,8);

clear x

clear t

I get the following error message:

 ------------

 Assertion detected at Fri Dec 05 10:28:33 2003

 ------------

 Assertion failed: hdr->in_use != 0, at line 1218 of file ".\mwmem.c".

 Attempt to free previously freed memory

 Configuration:

 MATLAB Version: 6.5.0.196271 (R13.0.1)

 Operating System: Microsoft Windows 2000

 Window System:Version 5.0 (Build 2195: Service Pack 3)

 Processor ID: x86 Family 6 Model 7 Stepping 3, GenuineIntel

 Virtual Machine:Java 1.3.1_01 with Sun Microsystems Inc. Java HotSpot(TM) Client VM

 (mixed mode)

 Stack Trace:

 [0] matlab.exe:_mnSignalHandler(0xffffffff, 0, 0, 1) + 592 bytes

 [1] matlab.exe:void __cdecl ThrowAssertion(void)(2, 0x7a748bc0, 0x65737341, 0x6f697472) + 162 bytes

 [2] matlab.exe:void __cdecl MATLABAssertFcn(char const *,char const *,int,char const *)(0x7a741868 ": hdr->in_use != 0,", 0x7a74100c ".\mwmem.c", 1218, 0x7a741938 "Attempt to free previously freed..") + 131 bytes

 [3] libut.dll:_ut_assertstr(0x7a741868 ": hdr->in_use != 0,", 0x7a74100c ".\mwmem.c", 1218, 0x7a741938 "Attempt to free previously freed..") + 25 bytes

 [4] libut.dll:_mw_free(0x01add730 "_ioFopenHelpPath", 5, 0x1983acf8 "D:\Applications\bin\win32\matlab..", 0x00dfcd34) + 542 bytes

 [5] libut.dll:_utFree(0x01add730 "_ioFopenHelpPath", 1, 0x1983acf8 "D:\Applications\bin\win32\matlab..", 0x00dfcd44) + 25 bytes

 [6] libmx.dll:_mxDestroyArrayContents(0x1983acf8 "D:\Applications\bin\win32\matlab..", 0x019a02b0, 0x00dfcd58, 0x7b111fde) + 209 bytes

 [snip]

Answer 1

[MathWorks Support Team]

This has been verified as a bug in the Signal Processing Toolbox 6.1 (R13SP1) in the way that BUFFER handles cell arrays.

As a workaround, use CELL2MAT to convert your n-by-1 cell array into a n-by-1 column vector.

a = {1;2;3;4;5;6;7};

b = cell2mat(a);

c = buffer(b,2)