Re: Show left hand side
- To: mathgroup at smc.vnet.net
- Subject: [mg111063] Re: Show left hand side
- From: "David Park" <djmpark at comcast.net>
- Date: Mon, 19 Jul 2010 02:08:32 -0400 (EDT)
I use multiple statements in one cell, with multiple outputs, quite often and don't see any problem with it. It's a good way to develop a calculation before moving it to a Module, or to develop a derivation or to just try out things. When everything is in one cell you can safely use % and %% without worrying about order of evaluation. You can intersperse Print statements if you want to annotate the output. You can keep adding further steps and reevaluating as a calculation is built up. You can add or remove ";"s as you want to see more or less. I never have any problem with Return being misinterpreted as a multiplication. It is far easier than using multiple cell evaluations or using a new Subsection or even selecting the correct set of cells. There is a subset of Mathematica users who see writing extended definitions and routines as a barrier. The multiple statement, single cell form is a good way to transition them to it, because it almost is a routine. David Park djmpark at comcast.net http://home.comcast.net/~djmpark/ From: Helen Read [mailto:hpr at together.net] On 7/17/2010 8:16 AM, Sam Takoy wrote: > Hi, > > When Mathematica prints an expression not terminated by a semicolon, I > find it hard to match up the output with what I was trying output when a > block of commands has many commands not terminated by a semicolon. I don't think it is a good idea to have a block of commands all in one cell that are not separated by semi-colons. As you point out, it is difficult to follow. Worse, it can easily lead to errors. For example two things that you intended as separate commands end up getting multiplied together. If you need to see the output of each command, put each input in a separate cell. Then you will have a sequence input/output, input/output, which is very easy to read and follow. If you find it tiresome to evaluate each input one by one, put them all in a section and select the cell bracket for the entire section. Then when you evaluate (Shift-Enter), everything that is selected will be evaluated. On the other hand, if you only to see output from the last command, put it all in a single cell, separating the commands with semi-colons (and no semi-colon on the last one). For a block of code that you will re-use with different input, write a function in the form of a Module or Block. Use Print within the Module (or Block) anywhere you want to see output. > Is there a way to get Mathematica to output the LHS so when I have > R=1+1 it outputs R = 2 or something like that. Print a Row. This is especially useful within a Module or Block. r = 1 + 1; Print[Row[{"r = ", r}]]; One last comment: it is a good habit to use lower case letters for your own variable and function names, to avoid inadvertent conflicts with built-in functions and symbols. I also think it makes it a bit easier to read your code that way -- it is immediately clear which functions and symbols you have defined yourself, and which ones are built-in. If you have very long function names, you can use what is sometimes called camel case. myVeryLongFunctionNameInCamelCase[x_,y_,z_]:= x^2+2y+z -- Helen Read