Contents

# Risinātājs

Opens the Solver dialog. A solver allows you to solve mathematical problems with multiple unknown variables and a set of constraints on the variables by goal-seeking methods.

Lai piekļūtu šai komandai...

#### From the menu bar:

Choose Tools - Solver.

#### From the tabbed interface:

Choose Tools - Solver.

On the Tools menu of the Tools tab, choose Solver.

#### From toolbars:

Solver

## Solver settings

### Target Cell

Enter or click the cell reference of the target cell. This field takes the address of the cell whose value is to be optimized.

### Optimize results to

- Maximum: Try to solve the equation for a maximum value of the target cell.

- Minimum: Try to solve the equation for a minimum value of the target cell.

- Value of: Try to solve the equation to approach a given value of the target cell.

  Enter the value or a cell reference in the text field.

### By Changing Cells

Enter the cell range that can be changed. These are the variables of the equations.

### Ierobežojošie nosacījumi

Add the set of constraints for the mathematical problem. Each constraint is represented by a cell reference (a variable), an operator, and a value.

- Cell reference: Enter a cell reference of the variable.

  Click the Shrink button to shrink or restore the dialog. You can click or select cells in the sheet. You can enter a cell reference manually in the input box.

- Operator: Select an operator from the list. Use Binary operator to restrict your variable to 0 or 1. Use the Integer operator to restrict your variable to take only integer values (no decimal part).

- Value: Enter a value or a cell reference. This field is ignored when the operator is Binary or Integer.

- Remove button: Click to remove the row from the list. Any rows from below this row move up.

You can set multiple conditions for a variable. For example, a variable in cell A1 that must be an integer less than 10. In that case, set two limiting conditions for A1.

### Opcijas

Opens the Solver Options dialog.

The Solver Options dialog let you select the different solver algorithms for either linear and non-linear problems and set their solving parameters.

### Solve

Click to solve the problem with the current settings. The dialog settings are retained until you close the current document.

## Lai atrisinātu vienādojumus ar risinātāju

The goal of the solver process is to find those variable values of an equation that result in an optimized value in the target cell, also named the "objective". You can choose whether the value in the target cell should be a maximum, a minimum, or approaching a given value.

The initial variable values are inserted in a rectangular cell range that you enter in the By changing cells box.

You can define a series of limiting conditions that set constraints for some cells. For example, you can set the constraint that one of the variables or cells must not be bigger than another variable, or not bigger than a given value. You can also define the constraint that one or more variables must be integers (values without decimals), or binary values (where only 0 and 1 are allowed).

## Using Non-Linear solvers

Regardless whether you use DEPS or SCO, you start by going to Tools - Solver and set the Cell to be optimized, the direction to go (minimization, maximization) and the cells to be modified to reach the goal. Then you go to the Options and specify the solver to be used and if necessary adjust the according parameters.

Parasti ierobežojumu sarakstu lieto, lai uzdotu iespējamo risinājumu diapazonu un sodītu noteiktus stāvokļus. Taču evolucionāro risinātāju DEPS un SCO gadījumā šie ierobežojumi arī norāda uzdevuma mainīgo robežas. Nejaušās algoritmu dabas dēļ ir ļoti ieteicams uzdot augšējās robežas visiem mainīgajiem (un, ja "Pieņemt vērtības kā nenegatīvas" ir izslēgts, arī apakšējās). Tām nav jābūt tuvām pašam risinājumam (kurš droši vien nav zināms), bet tām vajadzētu dot aptuvenu norādi, kāds ir sagaidāmais izmērs (0 ≤ mainīgais ≤ 1 vai varbūt -1000000 ≤ mainīgais ≤ 1000000).

Robežas tiek norādītas, izvēloties vienu vai vairākus mainīgos (kā diapazonu) kreisajā pusē un ievadot skaitlisku vērtību (nevis šūnu vai formulu) labajā pusē. Šādā veidā jūs varat arī izvēlēties vienu vai vairākus mainīgos, kas var būt tikai veseli vai bināri skaitļi.

Saistītie temati

Solver Options

Solver Algorithms Options

Wiki page on solvers and their algorithms