Problem

You've learned how to enter text from the previous recipe, but now you want to enter data other than text (e.g., numbers, dates, and currency).

Solution

Enter the data just as you would text and let Excel automatically figure out its type, or use the Format images/U2192.jpg border=0> Cells... menu to open a dialog box allowing you to manually format the data type for a cell.

Discussion

In the previous recipe, I had you simply enter text in cells. Whether you entered a word or a number, Excel automatically figured out what type of data you entered. In general, input starting with letters is automatically interpreted as text, and input starting with numbers is automatically interpreted as numeric. There are some special cases worth noting here. Preceding any string of charactersnumbers or letterswith the ' symbol forces Excel to interpret the data as text. Preceding a string of numbers with the `$` symbol forces Excel to interpret the data as currency. Using `E` (or `e`) while entering a number in scientific notation forces Excel to interpret the string as a number in scientific notation. Entering numbers with dashes between them will cause Excel to interpret the number as a date. I encourage you to try entering various types of data like those I describe here to see how Excel handles the data. In some cases you'll notice that Excel will reformat your data a little. For example, if you type `1.2345e3` in a cell, it will appear as `1.23E+3` in the cell and `1234.56` in the formula bar (when the cell is selected).

In general, Excel is pretty smart about interpreting the data type you intend; however, sometimes it does need a little help. Also, sometimes you may want to change the format of the data to give it an appearance other than the default appearance assigned to it by Excel. In these cases you can manually specify the type and format of data contained in cells by accessing the Format Cells dialog box . You can do so by selecting Format images/U2192.jpg border=0> Cells... from the menu or by using the shortcut key combination, Ctrl-1.

Figure 1-5 shows the Format Cells dialog box. Notice here I had a cell selected that contained the entry `1.2345e3`, which appears in the Sample area of the dialog box. This allows you to preview the results while making format changes.

I find that one of the most common uses of formatting tasks is specifying the number of decimal places to show for numbers. You can specify the number of decimal places to show by entering a value in the "Decimal places" field. Changing this setting is a format change only; it does not change the data itself. For example, if you enter `123.45678` in a cell and set the number of decimal places to 3, the cell will show `123.457` but the actual number is still stored as 123.45678, as can be seen in the formula bar when the cell is selected.

You can also select one of the categories shown in the Format Cells dialog box to set the type of data. If you click each category in the list, a short description and other formatting options will appear in the Format Cells dialog box. For example, if you select the Number category, the Format Cells dialog box will appear (see Figure 1-6).

The new formatting options appear on the right side of the dialog box, just under the "Decimal places" setting.

Format changes affect the currently selected cell and remain in effect until you change the format. If you set a cell to display Currency and then enter a new value in that cell, it will also be interpreted as currency.

Figure 1-5. Format cells dialog box

Figure 1-6. Format Cells with the Number category selected

You need not always use the Format Cells dialog box to change cell formatting. Some of these formatting operations have been assigned to toolbar buttons for convenience. Take a look at Figure 1-7 and notice the toolbar buttons that I highlighted. These specific buttons allow you to change some cell format properties with the click of a button.

Figure 1-7. Cell format toolbar

The $ button changes the cell format to currency while the % button changes the cell format to percentage; e.g., if you enter `0.38`, it will show up as `38%`. The two other highlighted buttons respectively increase and decrease the number of decimal places to show.

I should also point out that formatting changes take effect for all of the cells currently selected. So far, I've only discussed selecting a single cell; however, there are times when you may want to make changes to multiple cells all at one time. The next recipe explains how to select more than one cell at a time.

See Also

I find the Number, Percentage, and Scientific format categories more than adequate for most scientific and engineering computing tasks; however, there may be occasions when you want to set your own specific data format for a unique application. In this case, you can actually specify your own format template in the Format Cells dialog box by setting up format codes using the Custom format category. I won't go into the details here since it's fairly well documented in Excel's online help. To learn more, open the Excel Help task pane and do a search using the key phrase "Custom Formatting." In your search results, look for the topics entitled "Create or delete a custom number format" and "Number format code."

Using Excel

- Introduction
- Navigating the Interface
- Entering Data
- Setting Cell Data Types
- Selecting More Than a Single Cell
- Entering Formulas
- Exploring the R1C1 Cell Reference Style
- Referring to More Than a Single Cell
- Understanding Operator Precedence
- Using Exponents in Formulas
- Exploring Functions
- Formatting Your Spreadsheets
- Defining Custom Format Styles
- Leveraging Copy, Cut, Paste, and Paste Special
- Using Cell Names (Like Programming Variables)
- Validating Data
- Taking Advantage of Macros
- Adding Comments and Equation Notes
- Getting Help

Getting Acquainted with Visual Basic for Applications

- Introduction
- Navigating the VBA Editor
- Writing Functions and Subroutines
- Working with Data Types
- Defining Variables
- Defining Constants
- Using Arrays
- Commenting Code
- Spanning Long Statements over Multiple Lines
- Using Conditional Statements
- Using Loops
- Debugging VBA Code
- Exploring VBAs Built-in Functions
- Exploring Excel Objects
- Creating Your Own Objects in VBA
- VBA Help

Collecting and Cleaning Up Data

- Introduction
- Importing Data from Text Files
- Importing Data from Delimited Text Files
- Importing Data Using Drag-and-Drop
- Importing Data from Access Databases
- Importing Data from Web Pages
- Parsing Data
- Removing Weird Characters from Imported Text
- Converting Units
- Sorting Data
- Filtering Data
- Looking Up Values in Tables
- Retrieving Data from XML Files

Charting

- Introduction
- Creating Simple Charts
- Exploring Chart Styles
- Formatting Charts
- Customizing Chart Axes
- Setting Log or Semilog Scales
- Using Multiple Axes
- Changing the Type of an Existing Chart
- Combining Chart Types
- Building 3D Surface Plots
- Preparing Contour Plots
- Annotating Charts
- Saving Custom Chart Types
- Copying Charts to Word
- Recipe 4-14. Displaying Error Bars

Statistical Analysis

- Introduction
- Computing Summary Statistics
- Plotting Frequency Distributions
- Calculating Confidence Intervals
- Correlating Data
- Ranking and Percentiles
- Performing Statistical Tests
- Conducting ANOVA
- Generating Random Numbers
- Sampling Data

Time Series Analysis

- Introduction
- Plotting Time Series Data
- Adding Trendlines
- Computing Moving Averages
- Smoothing Data Using Weighted Averages
- Centering Data
- Detrending a Time Series
- Estimating Seasonal Indices
- Deseasonalization of a Time Series
- Forecasting
- Applying Discrete Fourier Transforms

Mathematical Functions

- Introduction
- Using Summation Functions
- Delving into Division
- Mastering Multiplication
- Exploring Exponential and Logarithmic Functions
- Using Trigonometry Functions
- Seeing Signs
- Getting to the Root of Things
- Rounding and Truncating Numbers
- Converting Between Number Systems
- Manipulating Matrices
- Building Support for Vectors
- Using Spreadsheet Functions in VBA Code
- Dealing with Complex Numbers

Curve Fitting and Regression

- Introduction
- Performing Linear Curve Fitting Using Excel Charts
- Constructing Your Own Linear Fit Using Spreadsheet Functions
- Using a Single Spreadsheet Function for Linear Curve Fitting
- Performing Multiple Linear Regression
- Generating Nonlinear Curve Fits Using Excel Charts
- Fitting Nonlinear Curves Using Solver
- Assessing Goodness of Fit
- Computing Confidence Intervals

Solving Equations

- Introduction
- Finding Roots Graphically
- Solving Nonlinear Equations Iteratively
- Automating Tedious Problems with VBA
- Solving Linear Systems
- Tackling Nonlinear Systems of Equations
- Using Classical Methods for Solving Equations

Numerical Integration and Differentiation

- Introduction
- Integrating a Definite Integral
- Implementing the Trapezoidal Rule in VBA
- Computing the Center of an Area Using Numerical Integration
- Calculating the Second Moment of an Area
- Dealing with Double Integrals
- Numerical Differentiation

Solving Ordinary Differential Equations

- Introduction
- Solving First-Order Initial Value Problems
- Applying the Runge-Kutta Method to Second-Order Initial Value Problems
- Tackling Coupled Equations
- Shooting Boundary Value Problems

Solving Partial Differential Equations

- Introduction
- Leveraging Excel to Directly Solve Finite Difference Equations
- Recruiting Solver to Iteratively Solve Finite Difference Equations
- Solving Initial Value Problems
- Using Excel to Help Solve Problems Formulated Using the Finite Element Method

Performing Optimization Analyses in Excel

- Introduction
- Using Excel for Traditional Linear Programming
- Exploring Resource Allocation Optimization Problems
- Getting More Realistic Results with Integer Constraints
- Tackling Troublesome Problems
- Optimizing Engineering Design Problems
- Understanding Solver Reports
- Programming a Genetic Algorithm for Optimization

Introduction to Financial Calculations

- Introduction
- Computing Present Value
- Calculating Future Value
- Figuring Out Required Rate of Return
- Doubling Your Money
- Determining Monthly Payments
- Considering Cash Flow Alternatives
- Achieving a Certain Future Value
- Assessing Net Present Worth
- Estimating Rate of Return
- Solving Inverse Problems
- Figuring a Break-Even Point

Index

Excel Scientific and Engineering Cookbook (Cookbooks (OReilly))

ISBN: 0596008791

EAN: 2147483647

EAN: 2147483647

Year: N/A

Pages: 206

Pages: 206

Authors: David M Bourg

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