number of a row in an array

#1 Posted: 3/26/2021 11:40:35 PM

7 likes in 28 posts.

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Hi guys

Do you know how to get the number of a row in an array?
ie I have a 5 * 2 array, I want to know what is the number of a particular row

¿Cómo se obtiene el número de una fila, de una matriz?
How do you get the number of a row, of a matrix?
I do not speak English, I hope you can understand me with the following image

[albumimg]1629[/albumimg]

#2 Posted: 3/27/2021 12:33:17 AM

NDTM Amarasekera

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Hello Valentino!
This snippet downloaded from the forum long time back.
Credit to the author, but cannot remember.
There may be other short cuts too.

Cheers.....

Look within!... The secret is inside you. Best Regards Eng. NDTM Amarasekera - Sri Lanka

2 users liked this post

Erick Valentino 5/6/2021 7:32:00 AM, Oscar Campo 5/10/2024 7:12:00 PM

#3 Posted: 3/27/2021 7:32:48 AM

NDTM Amarasekera

130 likes in 352 posts.

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To find the indices of an array of values.
Cheers.....

Find_Row_Num.sm (95 KiB) downloaded 57 time(s).

Look within!... The secret is inside you. Best Regards Eng. NDTM Amarasekera - Sri Lanka

3 users liked this post

sergio 3/27/2021 8:42:00 AM, Erick Valentino 5/6/2021 7:32:00 AM, Oscar Campo 5/10/2024 7:12:00 PM

#4 Posted: 3/27/2021 8:33:47 AM

Jean Giraud

983 likes in 6866 posts.

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Wrote
Do you know how to get the number of a row in an array?

These 4 are from a much larger compendium.
You will go a long route with them.
Jean

Utilities Matrix Truth Table [Locate row_col].sm (45 KiB) downloaded 40 time(s).
Utilities Matrix Locate Array1 Array2.sm (70 KiB) downloaded 33 time(s).
Utilities Matrix Truth Table [Locate row_col] COMPANION.sm (153 KiB) downloaded 43 time(s).
Utilities Matrix Treasury_1.sm (423 KiB) downloaded 33 time(s).

1 users liked this post

Erick Valentino 5/6/2021 7:32:00 AM

#5 Posted: 5/6/2021 7:35:13 AM

Erick Valentino

7 likes in 28 posts.

Group: User

Wrote
Hello Valentino!
This snippet downloaded from the forum long time back.
Credit to the author, but cannot remember.
There may be other short cuts too.

Cheers.....

Thank you very much, it worked perfectly for me,
the method you teach is very useful.
Thanks for taking the time and sharing your ideas.

#6 Posted: 5/6/2021 8:21:02 AM

Martin_B

21 likes in 84 posts.

Group: User

Alternative (needs special functions plugin):

Or in one line:

#7 Posted: 5/6/2021 9:49:36 AM

Jean Giraud

983 likes in 6866 posts.

Group: User

Wrote
Do you know how to get the number of a row in an array?
i.e: I have a 5 * 2 array, I want to know what is the number of a particular row

#8 Posted: 7/27/2023 4:04:49 PM

Beyaz

0 likes in 19 posts.

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hey,

i have a some problem.
i hope someone can solve this problem too.

in the first exampe "match" its not working but in the second example it works. i dont know why

#9 Posted: 7/27/2023 10:14:46 PM

overlord

547 likes in 1330 posts.

Group: Moderator

Wrote
hey,

i have a some problem.
i hope someone can solve this problem too.

in the first exampe "match" its not working but in the second example it works. i dont know why

Hi Beyaz,
For first warning, row() expect a real pure number for second argument.
Your findrows() result is a number with N unit.

Due to your second problem;
I think commas in your subscripts makes the bug.
When they are deleted, your function match() works.

Regards

PS: Please provide your problematic file next time.
Rewriting your entire screenshot is cumbersome.

match.sm (10 KiB) downloaded 31 time(s).

#10 Posted: 7/28/2023 9:27:38 AM

Jean Giraud

983 likes in 6866 posts.

Group: User

More utilities were designed and available.
These 4 will go a long route ... projects.
Created Studio, sanity checked Solver 30405.

Utilities Matrix Locate Array1 Array2.sm (70 KiB) downloaded 28 time(s).
Utilities Matrix FindIndex DUAL COMPANION Copy.sm (108 KiB) downloaded 24 time(s).
Utilities Matrix FindIndexKey COMPANION QUICK Copy.sm (89 KiB) downloaded 26 time(s).
Utilities Matrix FindIndexKey COMPANION QUICK.sm (89 KiB) downloaded 28 time(s).

#11 Posted: 7/28/2023 4:32:39 PM

Beyaz

0 likes in 19 posts.

Group: User

Wrote

Wrote
hey,

i have a some problem.
i hope someone can solve this problem too.

in the first exampe "match" its not working but in the second example it works. i dont know why

Hi Beyaz,
For first warning, row() expect a real pure number for second argument.
Your findrows() result is a number with N unit.

Due to your second problem;
I think commas in your subscripts makes the bug.
When they are deleted, your function match() works.

Regards

PS: Please provide your problematic file next time.
Rewriting your entire screenshot is cumbersome.

match.sm (10 KiB) downloaded 31 time(s).

thanks overlord
sorry, you are right, next time i will add the file.

i tried it but it doesnt work. this time i add the file.
vogt.sm (636 KiB) downloaded 25 time(s).

//I solved it like this

#12 Posted: 7/28/2023 5:03:03 PM

overlord

547 likes in 1330 posts.

Group: Moderator

Your while loop shouldn't produce E.rkx.
At least my computer doesn't.
There should be an E.rkx output at end of it.

I would solve eval() problem like this.

Regards

#13 Posted: 7/29/2023 8:22:05 AM

Jean Giraud

983 likes in 6866 posts.

Group: User

Attach an image of a typical 6 x 4 matrix 4 decimals.
From there, say what you want to extract.
That will ease the guidance, while avoiding confusion.

#14 Posted: 1/5/2024 4:37:40 PM

Beyaz

0 likes in 19 posts.

Group: User

hey guys,

Your suggestions were very helpful, but is it possible to rewrite the function so that strings are also can be match.
Im looking for the Index of "b" ->[2]

KLED.sm (4 KiB) downloaded 22 time(s).

#15 Posted: 1/6/2024 3:48:08 AM

Martin Kraska

1222 likes in 2150 posts.

Group: Moderator

The result of findrows() is a matrix, even if there is only one match (exept for no matches, then the result is the number zero)
Converting it to a scalar, seems to help. The same could be applied to the overall result to remove the matrix.

Yet, there is a shorter way to get the index. This, however, won't work for multiple matches.

File not found.File not found.

Martin Kraska Pre-configured portable distribution of SMath Studio: https://en.smath.info/wiki/SMath%20with%20Plugins.ashx

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