how to simplify multi- if statement

2012 12 6
2 个回答
回答已采纳
1 次查看（30 天）

0 个投票

I'm trying to do the following work, given a string of 'ABCDE' etc,
for each letter, it will be assigned with a unique number.
How would I do it without putting 26 if and else if statement in a simple way?
I'm thinking of two matrices. But it may not be on the right track. Can anyone help with this case? Thanx in advance!

1 个评论
显示 -1更早的评论 隐藏 -1更早的评论

Qian
Qian 2012-12-6
sorry for the bad description. I'm saying, the assignments between letters and numbers are given, what I want is to replace letter with numbers in the given way. The only method I was using is the if and else if statement with one-to-one assignment, but with longer string of letters, I don't really like to put 26 statement, is there any quicker way?

请先登录，再进行评论。

请先登录，再回答此问题。

 采纳的回答

Matt Fig
Matt Fig 2012-12-6
编辑：Matt Fig 2012-12-6

0 个投票

STR = char(65:90)
KEY = randi(10000,1,length(STR))
But what are you going to do with these that you would need an IF block for? Are you going to do something like encode a given string?
g_str = upper('Hello')
k_str = KEY(g_str-64)

8 个评论
显示 6更早的评论 隐藏 6更早的评论

Qian
Qian 2012-12-6
thanx for that as well, but sorry for my bad description. I'm saying, the assignments between letters and numbers are given, what I want is to replace letter with numbers in the given way. The only method I was using is the if and else if statement with one-to-one assignment, but with longer string of letters, I don't really like to put 26 statement, is there any quicker way?
Matt Fig
Matt Fig 2012-12-6
That is what my second bit of code does..... Just imagine the KEY is the given set of numbers for all the letters in STR. Then to replace the letters in g_str, index into KEY like I did.
Qian
Qian 2012-12-6
Yep, I think I see what u meant now. Thanx!
Qian
Qian 2012-12-6
can I ask one more question, why is it -64?
Qian
Qian 2012-12-6
is it because u used char function?
Qian
Qian 2012-12-6
I think that's still not going to solve my problem fully, since My string is not in alpha beta order, and it's not fully 26 letters.
Matt Fig
Matt Fig 2012-12-6
But the same concept should apply. I subtracted 64 because we need to index starting from 1 and the ascii alphabet starts at 65.
Jos (10584)
Jos (10584) 2012-12-6
Using randi, it is not guaranteed that each character in STR is mapped onto a unique value ...

请先登录，再进行评论。

更多回答（1 个）

Rick Rosson
Rick Rosson 2012-12-6

0 个投票

aStr = 'ABCDE';
x = uint8(aStr) - 64;

1 个评论
显示 -1更早的评论 隐藏 -1更早的评论

Qian
Qian 2012-12-6
thanx for that, but the problem is ABCDE are not assigned to patterned numbers, but some random numbers, for instance A=14, B=23, C=1, D=4,E=34 etc.

请先登录，再进行评论。

类别

在 帮助中心 和 File Exchange 中查找有关 Characters and Strings 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by