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Miscellaneous Features
X& f8 \7 _. D: Q# rYou may have discovered by now that MATLAB is case sensitive, that is 8 d5 l! ?, W A9 a4 s9 g, C
4 b& I- z5 R0 O+ H8 M/ E"a" is not the same as "A."
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If this proves to be an annoyance, the command
% |; R! e+ b% lcasesen
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will toggle the case sensitivity off and on.
& I* D- T1 t) G% r1 ?6 ?8 dThe MATLAB display only shows 5 digits in the default mode. The fact is that MATLAB always keeps and computes in a double precision 16 decimal places and rounds the display to 4 digits. The command
0 h' N* K0 y1 K, f; K! K' ?, _* ]5 X0 y! h
format long
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3 y8 R+ h" C' {) B' E' `0 L9 E5 k- ?will switch to display all 16 digits and
: o! k. T, f2 h! `1 n6 Dformat short
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will return to the shorter display. It is also possible to toggle back and forth in the scientific notation display with the commands
" q6 p' u1 o0 |" X N+ o- z! t7 k0 D: h uformat short e( [6 }' i2 }. V0 l5 m5 n
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and 6 z5 u7 O1 U8 C
format long e' w r% _2 b/ g, I; x; A! W
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It is not always necessary for MATLAB to display the results of a command to the screen. If you do not want the matrix A displayed, put a semicolon after it, A;. When MATLAB is ready to proceed, the prompt >> will appear. Try this on a matrix right now. : `* ]1 G: J4 w' f6 E- ~) J& F
6 Q s7 O$ z: {2 KSometimes you will have spent much time creating matrices in the course of your MATLAB session and you would like to use these same matrices in your next session. You can save these values in a file by typing K, K6 t3 _ @* [9 E
u |& y* \, |2 O* Y% O; Y8 g) f0 Fsave filename( [ r* s, a( r9 E y
5 h! W( W0 e+ Y5 U# _This creates a file " X! r! r0 @- V# \* y5 I" l
O7 V6 H6 c1 s/ A0 Rfilename.mat
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which contains the values of the variables from your session. If you do not want to save all variables there are two options. One is to clear the variables off with the command 9 C# l( s/ t$ z
clear a b c
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5 D. W! N4 u7 b1 [3 p; Kwhich will remove the variables a,b,c. The other option is to use the command
/ V$ ?+ J" n+ |! bsave x y z! E, o! ?& a& Z9 [2 d
; h) A- b7 A0 m0 Q* d( y0 u/ Fwhich will save the variables x,y,z in the file filename.mat. The variables can be reloaded in a future session by typing
/ H2 o- V+ B$ `# N# Oload filename
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; u2 ^, x& z T% t# C3 HWhen you are ready to print out the results of a session, you can store the results in a file and print the file from the operating system using the "print" command appropriate for your operating system. The file is created using the command # a- r& X# f1 C) u% l
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diary filename- A0 G8 h: M$ A% G; z# O
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Once a file name has been established you can toggle the diary with the commands
' s& D- y0 t! R* G0 _diary on
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and
( w* h6 v9 X1 w8 Y) \- Fdiary off" H, F% f0 H: v8 q' Z$ q$ ?5 b/ H
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This will copy anything which goes to the screen (other than graphics) to the specified file. Since this is an ordinary ASCII file, you can edit it later. Discussion of print out for graphics is deferred to the project "Graphics" where MATLAB's graphics commands are presented.
4 W4 |; S7 c2 PSome of you may be fortunate enough to be using a Macintosh or a Sun computer with a window system that allows you to quickly move in and out of MATLAB for editing, printing, or other processes at the system level. For those of you who are not so fortunate, MATLAB has a feature which allows you to do some of these tasks directly from MATLAB. Let us suppose that you would like to edit a file named myfile.m and that your editor executes on the command ed. The MATLAB command
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Q% u/ z) Z& l E1 q!ed myfile.m
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will bring up your editor and you can now work in it as you usually would. Obviously the exclamation point is the critical feature here. When you are done editing, exit your editor as you usually would, and you will find that you are back in your MATLAB session. You can use the ! with many operating system commands. |
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