## equation solving – Duplicate RowReduce function

Writing:

``````AA = {{a, b, c, d}, {e, f, g, h}, {i, j, k, l}};
AAold = AA;
nn = Length[AA];
For[ii = 1, ii <= nn, ii++,
If[Quiet[IntegerQ[AA[[ii, ii]]^0]] == False,
kk = ii + 1;
While[kk < nn && Quiet[IntegerQ[AA[[kk, ii]]^0]] == False,
kk = kk + 1
];
If[kk > nn,
Print["Singular matrix"];
Abort[]
];
For[jj = 1, jj <= nn + 1, jj++,
ll = AA[[ii, jj]];
AA[[ii, jj]] = AA[[kk, jj]];
AA[[kk, jj]] = ll
]
];
For[jj = 1, jj <= nn, jj++,
If[ii != jj,
ll = AA[[jj, ii]]/AA[[ii, ii]];
For[kk = 1, kk <= nn + 1, kk++,
AA[[jj, kk]] = AA[[jj, kk]] - AA[[ii, kk]] ll
]
]
]
];
For[ii = 1, ii <= nn, ii++,
AA[[ii, nn + 1]] = AA[[ii, nn + 1]]/AA[[ii, ii]];
AA[[ii, ii]] = 1
];
FullSimplify[AA == RowReduce[AAold]]
``````

I get

True

and the same if I define:

``````AA = {{0, b, c, d}, {e, f, g, h}, {i, j, k, l}};
``````

or:

``````AA = {{0, b, c, d}, {0, f, g, h}, {i, j, k, l}};
``````

On the other hand, if I define:

``````AA = {{0, b, c, d}, {0, f, g, h}, {0, j, k, l}};
``````

I would expect as output:

Singular matrix

when I get error messages instead. Could anyone kindly tell me how to fix this code without twisting it?

Thanks!

## Deleter more than 50 e-mails in gmail in 2020 [duplicate]

Last time when I selected the e-mails on a page to delete, after selecting 50, gmail offered that it could mark all the e-mails having that label.

Now it does not.

How can I select all that 9000 e-mails now?

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What will be the correct format for my URL (Here, I am trying to target the keyword ‘abcxyz’):

www.abcxyz.com/abc-xyz.php/……………….

www.abcxyz.com/custom-abc-xyz.php/…………

Please suggest if any one is correct or not for my website?

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I’ve been trying to make use of the Shapechange spell as a 9th level spell with a Druid class, but concentration seems to be a major issue. Say I transform into a Phoenix, can I use the 3 Legendary Resistance to automatically succeed in a damaging saving throw three times to prolong the form? This would make Shapechange viable for melee characters for atleast a slightly longer period than a single turn.

## What happens if user generated content is duplicate?

y u no do it?

Advertise virtually anything here, with CPM banner ads, CPM email ads and CPC contextual links. You can target relevant areas of the site and show ads based on geographical location of the user if you wish.

Starts at just \$1 per CPM or \$0.10 per CPC.

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Should I explain this in my cover letter, incase they notice a deposit that is not in my parents name?

## count duplicate entries sharepoint – SharePoint Stack Exchange

I need a little help please.
I’m using SharePoint 2013, with no SharePoint designer (disabled by the administrator).
I have a list, in which a have duplicated entries in a column named Title. I need to count those duplicates so I can apply a filter and view just those who have 3 or more occurrences. is it possible?

## office365 – Excel – Different highlighting for different pairs of duplicate values

0

I have an Excel file that contains the data of a website’s users. In column A I have their username, and in column B I have their email address. Unfortunately, there are many duplicates: both inside the same column, and across.

Example:

1. Thelegend28 | myemail@gmail.com
3. l33tu53r | iml33t@live.com
4. Thelegend28 | duplicatemail@hotmail.com
5. 2l33t4u | iml33t@live.com

As you can see, not only do I have users that are registered twice with the same username and email (2. and 6.), but I also sometimes have different unique usernames linked to the same email (3. and 5.) and usernames that are linked to more than one address (1. and 4.).

What I need to do, if possible, is format these three occurrences differently.

Of course, any help is greatly appreciated. I’m just a noob, but I’m trying to learn. Thank you all in advance.

## How to duplicate UpValue of one function to another?

Let’s say I have defined a function `zO` for the following up-values

``````zO/:zO[x_]+zO[y_]:=zO[x+y];
zO/:zO[x_]+zo[y_]:=zO[x+y];
zO/:zO[x_]-zO[y_]:=zO[x+y];
``````

Now I want to define another function `zOE` which have the same up-values. How can I do this without copying and modifying the above rules?

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