• ## Rearranging dynamic equationsAugust 31

I'm deriving dynamic equations for a simple system, this is what I get: How can I rearrange these 2 equations into the form like this: My code is: Subscript[x, 1] = -Subscript[q, 1][t] R; Subscript[y, 1] = 0; Subscript[x, 2] = Subscript[x, 1] + Subsc

• ## Find inverse of the parametric matrix [on hold]August 31

I want to calculate the bellow parametric matric but I faced with this error: any suggestion?? Inverse::sing: Matrix {{-0.00950009,2.40002,0.000800379,0.0352495,1.80002,0.,5.00005,0.,0.0891225,0.,0.,0.},<<10>>,{0.,0.,0.,0.,0.,-1.,0.,0.,0. +1.

• ## How to find equation tangent to a function? August 31

A common problem in the derivative section of calculus texts is "find the equation of the line that is tangent to the curve $y = \ldots$ at the point $P$." To find the line that is tangent to $y = 2 x \sin x$ at $(\pi/2,\pi)$, I'd do something l

• ## Conditional deleting pairs inside a list of pairs August 31

This question already has an answer here: Removing an ordered pair from a list of ordered pairs if the second element in the list is Less than a Value 1 answer I have a list of pairs for example like following: list={{1,0.001},{10^(-7),0.001},{0.01,0

• ## Casting an optimization problem into least-squares form for Levenberg-Marquardt August 31

I wrote a function in Matlab that optimizes another user defined function using lsqnonlin with 'levenberg-marquardt' option. Now, I'd like to use the first to optimize a user defined function written in Mathematica. An alternative solution would be t

• ## Interacting with the vertices of a polygon and points on a circleAugust 31

I want to create an interactive module, where I can plot the vertices of polygon and some points on a circle(for example, suppose a triangle and 3 points on the circle) and move the vertices of the polygon and use the co-ordinates of the vertices of

• ## Question about transforming a list of rulesAugust 31

Consider the following list: {{"id" -> "8792584", "name" -> "Maybank Championship Malaysia", {"marketCount" -> 22, "competitionRegion" -> "GBR"}}, {"id" -> &quo

• ## Error with FindMinimum. The Message is FindMinimum::cnpconsAugust 31

I want to run a rather demanding check of fesibility. I have 3565 nonegativity constraints for my variables and one that makes them sum to a certain budget they shall not surpass. Then I have one inequality constraint that calculates whether or not a

• ## Count values inside sublists separatelyAugust 30

I've the following problem: given a nested list like this: a={{1,2,3,2,1},{2,3,4,6,4,3,2},{4,5,12,5,4}}; How can I count, in each sublist, those values that are following a particular rule, like the values bigger or equal than half the maximum value

• ## How do I run 1-855 data points( imported from excel sheet) into a formula to obtain value for each data point?August 30

I am very new to Mathematica and I just couldn't figure out the solution for the following problem. I have two columns in an Excel file. I have imported the 1st column as temp (1- 855 data points), and the 2nd as den (1-855 data points). I am trying

• ## Problems with using apex to get metadataAugust 30

1.When I query the objects using Schema.getGlobalDescribe() I get wierd objects like "ApexTestQueueItem", "Announcement", "AccountContactRole", "Account_Escalation__c". I basically only want the standard objects and

• ## PlaceHolder for Apex:inputTextAreaAugust 30

Pass through attribute to display Ghost text is not working for Apex:inputTextArea. I mentioned docuType as 'Html-5.0' in apex page correctly. Example : <apex:inputTextarea value="{!test}" html-placeholder="test placeholder"> Any

• ## Record type profile and page layout settingAugust 30

I created a new record type and during the process I added it to profiles and assigned the new record type page layout. This was done in DEV. When I move the record type from DEV to FUll sandbox using change set , I do not see the record type appear

• ## Problem linking to a static resource imageAugust 30

I went through a lot of threads of people explaining how to link to a static resource image in your CSS. My code looks fine to me, yet it doesn't work. I have put the css file in a folder together with the images folder(which holds the manager_headsh

• ## Unable to redirect to specific page using flow finish locationAugust 30

I have created a flow and trying to pass a value to a finish location using visualforce page. In the finish page i am able to get the value but unable to redirect the customer to that particular record. Value is coming in the createdid.Using the belo

• ## Trigger on custom object tasksAugust 30

I would like for a field "contacted last 90 days" to be checked if an activity has been performed in that time frame and to uncheck if 90 days has lapsed. If a user hits the log a call or send an email under the activity history is it possible t

• ## Getting error when using Salesforce-Test-Factory to create UsersAugust 30

I just installed Daniel Hoechst's test factory into my sandbox and am trying to use it to create test data for the following objects: User CollaborationGroup PermissionSet I'm getting the following error when creating users: System.SObjectException:

• ## Lightning: Get list view recordsAugust 30

How can one get ALL the records from a list view in a visualforce page running in Lightning? (Since no checkbox for selecting are available) Similar old question. With an adaptation from that question's answer, I have: public SomeClass(ApexPages.Stan

• ## Account that has related contacts should not be deletedAugust 29

I need to write a trigger in which if an account that has related contacts and the user tries to delete that account it throws you an error.. trigger DoNotDeleteAccountHavingRelatedContact on Account (before insert, before update) { List<Account> ac

• ## How do I change Record Type in Salesforce1?August 29

I feel I'm missing something simple here. From the UI, I can change the record type by using the "change" link in the view layout. I can't see a way of doing it from the Salesforce1 app.