# interpolation

1. ### Bilinear interpolation excel

I need to interpolate data from my table and I already have a way of doing so, which I learned from: https://www.engineerexcel.com/bilinear-interpolation-excel/ However, I wanted to incorporate it to my workbook in a way it can automatically fill in the values, since I have many similar tables...
2. ### Fixing my interpolation function.

So here's the deal, I work for a company that does "floor lifting". I.e. when a house has sunk we come in and do measurements, and give people an estimate of what we can do, and a recommendation. One way we collect measurements is by placing different height values at x, y locations in an excel...
3. ### Excel VBA Cubic Spline Interpolation

Hi Guys, By referring to the older post, I found something below as Cubic Spline Interpolation. The formula I found was s(x) = a(x-xi)^3+ b(x-xi)^2 + c(x-xi) + d, I would like to understand how it translate to the algorithm below. Much Appreciate. Function spline(periodcol As Range, ratecol...
4. ### Interpolation problem

How to get an interpolation for multiple variables. CFM, Outdoor Temperature, Wet Temperature, and Dry Temperature are given. Trying to get an interpolation for Total Capacity and Sensible Ratio. So an example would be, what is the Total Capacity and Sensible ratio when CFM=1100, Wet...
5. ### linear interpolation

Hi, I have a vba program, and need to do linear interpolation. There is are x and y values, but the values are not always the same so I need to have some function or Sub routine. I looked on the internet but couldn't find anything. It would be nice to use a custom program rather than a...
6. ### Extrapolation over random blank lines

Hi all, Please can someone offer me some help? I have the following spreadsheet (below), it has a list of times with associated ranges, the time goes up in seconds (every second) the range if whatever is measured, always decreasing. Every so often the data received is missed, so I get blank...
7. ### Three part interpolation

I have a table representing three variables (d/t, L/d, and A). I have calculated values of d/t and L/d, and I need to find the corresponding value of A. My calculated value of d/T = 6.89 and L/d = 49.38. Below is the portion of my table. d/T L/d A 5 10.00 4.59E-02 5 30.00...
8. ### Linear interpolation with vlookup

Hello, I am trying to get an excel formula that will do linear interpolation for me. The data is set up as follows. <colgroup><col width="83" style="width: 62pt; mso-width-source: userset; mso-width-alt: 3035;" span="2"> <tbody> 1W 0.24 1M 0.26 2M 0.27 3M 0.31...
9. ### Interpolating Data From a Table

Hi Guys, I've recorded engine data and two of the variables recorded were engine speed and coolant temperature. To determine friction torque, the table below needs to be used: <colgroup><col><col><col span="16"></colgroup><tbody> Engine Speed 400 800 1000 1100 1200 1300 1400 1500 1600 1800...
10. ### Linear Interpolation of Data

I am trying to write a formula which will linearly interpolate random sets of data in a table. For example, when used on the following table: <tbody> 0 1 2 3 4 5 15 20 0 10 0 15 20 5 20 </tbody> The output (in a separate table) should be: <tbody> 0 1 2 3 4 5 10 15 20...
11. ### Calculating Weighted Average of a Data Subset

Hi, I have a dataset with a variable versus depth (see below example). I want to calculate a weighted average of a calculated subset of these data, for example, the weighted average from 3.2 to, say, 8.7. I know how to calculate the weighted average of the full dataset, but not a subset, which...
12. ### VBA coding- generate a series of column data

Hello everyone, I am in need of your experts' assistance to teach me how to use the VBA program efficiently. Currently, I am trying to create a simple hydrograph with a specific condition: time of peak will be at the 1/4 of total time. My base data will be the USGS Dimensionless Unit...
13. ### Non linear but linear Interpolation

If my title caught your attention, please read further. I am not looking for elegance, but I am looking for a fast way to go through the data. I have 19914 lines (yes 19914 rows) of data that are separated into 3 columns Column A: Known Depth Column B: Known Age Column C: Known Depth (but points...
14. ### Linear Interpolation. From target, minimum, maximum, and step values

Hey there, guys! I'm struggling with a certain issue a bit. I need to calculate monthly bonuses in Excel in an automated way. Which basically means I need to answer the following question: "If we know minimum and maximum bonus amounts, starting target achievement, and step value, how much the...
15. ### INTERPOLATE function from previous version of Excel does not match FORECAST or GROWTH functions

I've searched the internet but have been unable to find a function that mirrors the INTERPOLATE function from previous versions of Excel. This is the old formula: =interpolate(E14,USD_Date, USD_ask, 2) This is the new formula (which doesn't match the old) =FORECAST(G13,USD_bid,USD_dates) Does...
16. ### Cubic Spline VBA code

Hi Guys, I have been searching the net for a piecewise cubic spline fitting vba code in which I can specify the knots in the curve. Does anyone have it available? I have had no luck finding it so far. All I get is cubic spline codes without having the flexibility to do it piecewise. I am...
17. ### Hydro-logic data Interpolation en Excell 2007

I have some excel Hydrologic data. But there are some missing data. I want to find what is the procedure od data interpolatiion. Please help me. <colgroup><col width="64" span="2" style="width:48pt"> </colgroup><tbody> Distance Elevation 100 2 110 -2 120 -3...
18. ### 1,000 missing survey data points to be fixed by interpolation

Hello experts, Tried all methods without success I have large data of around 10,000 drainage pipe segments and 10,000 junctions in ArcGIS layer The problem is: due to some reason certain junctions could not be accessed for survey, thus 1,000+ entries are missing for pipes (up stream and d/s...
19. ### Multiple Linear Interpolations on a Dynamic Range

Hello all, I have a VBA problem that I hope (and given the quality of some of the posts I have read, am quite sure) is solvable. I need to perform a linear interpolation using a 3 column range of cells, where the first column is an identifier for different data sets (see example below). The...
20. ### Reading data from a graph

I have a set of data that I have plotted in a graph. I have about 10-15 data points, the graph has couple of bends in it which I am very keen to preserve. I need to be able to identify y-values corresponding to x-values between my known data points. Is there any smart way in Excel to handle...