Use Is_String to Check if a Variable Is a String in PHP

The is_string() PHP function is used to check if a type of variable is a  string. A string is a data type, such as floating point or integer, but it represents text rather than numbers. A string uses a set of characters that includes spaces and numbers. For instance, an address such as 1234 Broadway and the sentence I ate 3 hotdogs contain numbers that should be treated as text, not as numbers. How to Use the Function Is_string is used within an if () statement to treat strings in one way and non-strings in another. It returns true or false. For example: ?php if (is_string(23)) {echo Yes;} else {echo No;}? The code above should output No because 23 is not a string. Lets try this again: ?php if (is_string(Hello World)) {echo Yes;} else {echo No;}? Since Hello World is a string, this would echo Yes. Specifying a String A string can be specified in four ways: Single quotedDouble quoted  Heredoc syntaxNowdoc Syntax Each of these methods requires strict adherence  to PHP rules, which are available at the PHP website. The simplest method, single-quoted strings, requires special treatment when literal single quotation marks or literal backslashes appear in the string. Include a backslash in front of the single quotation mark or backslash within the string. The example below illustrates this treatment: ?php//  Outputs:  Arnold said:  Ill  be  backecho  Arnold said:  I\ll  be  back;//  Outputs:  I  deleted  C:\*.*?echo  I  deleted  C:\\*.*?;? Similar Functions is_float() – determines if the type of variable is floatis_int() – determines if the type of variable is integeris_bool() – determines if a variable is a booleanis_object() – determines if a variable is an objectis_array() – determines if a variable is an arrayis_numeric() – determines if a value is a number or a numeric string

Thematic Essay The Veldt - 1165 Words

Thematic Essay Draft Imagine you re in a silent dead house The only noise you hear is yourself breathing. You hear yourself breathing in and out as you walk around with everything off. You turned everything off and it feels like there s dead body everywhere. Your kids are begging you to turn everything back on not wanting to leave the nursery. This is what happens in the book â€Å"The Veldt† by Ray Bradbury is about the family and their kids have this room that is called the nursery. In the nursery the point is to travel where ever you want but you stay in the house you just see what is looks like. Their kids Wendy and Peter don t use it for that reason. They only go to one place and one place only and that is Africa. One thing that happens in this book is that the kids are too obsessed with technology like the nursery which is to learn about other places and what they they look like and what it feels like, but that’s not what they do and things are getting out of control with them always visiting Africa. The children are becoming too obsessed with the technology and its affecting their learning on other places. They aren’t using the nursery for the things that they need to learn about. They are just using it for their entertainment and not for learning basing. Although some say that it is more out of hate then technology that is why they are changing is because they are hating their parents because they won t let them do what they want to do. Like how their dad wouldn’t

Electrocardiogram Essay Example For Students

Electrocardiogram Essay Electrocardiogram LabIntroductionElectrocardiograms are used to obtain information about the function of the heart. An ECG is a recording of the electrical activity of the heart made from electrodes placed on the surface of the skin. Salt solutions are good conductors of electricity and can transfer electrical activity to the skins surface. An ECG tracing shows the sum of the electrical potentials generated by all the cells of the heart at any moment (Silverthorn, 1998). Each point reflects depolarization or repolarization of a portion of the heart. Depolarization is the signal for contraction. There are three major components of an ECG: the p waves, which corresponds to depolarization of the atria (Silverthorn, 1998). The qrs complex represents the progressive wave of ventricular depolarization (Silverthorn, 1998). And the t wave, represents the repolarization of the ventricles. When recording an ECG, one active surface electrode is the positive and the other electrode is negative w hile the third electrode is inactive. These electrodes are known as leads. Twelve leads are now used to record ECG: the three limb electrodes plus the nine more electrodes placed on the chest and trunk. ECGS recorded from the different lead look different and give information about different regions of the heart (Purves, 1998). An ECG provides information on heart rate and rhythm, conduction velocity, and even the condition of the tissues within the heart. Although obtaining and ECG is simple, interpreting some of its subtleties can be quite complicated. PurposeTo understand the electrical and mechanical events accociated with an ECG tracing (DiFiori and Jarrell, 1998). To record and interpret ECG tracings under a variety of physiological situations (DiFiori and Jarrell, 1998). To determine how changes in an ECG can lead to changes in the heart rate (DiFiori and Jarrell, 1998). 1). What is the effect of the heart rate on a person who is sitting as opposed to exercising?Hypothesisthe heart rate is faster in a person who is exercising. 2) What is the effect of the heart rate on a person who is sitting as opposed to a person demonstrating biofeedback?Hypothesisthe heart rate could be the same if the individual is not totally relaxed, but if the person goes to his or her special place thats very relaxing for them, the heart while performing biofeedback could be lower than a person sitting down. MethodsSet up an individual to record a normal ECG by placing a white electrode on the wrist, a black electrode on the right ankle, and a red electrode on the lateral malleolus. Plug the electrodes into port number two and choose lesson five and press setup. The biopac unit will check the leads and adjust the recording on the screen. When your patient is still, press the record button and the biopac unit will record for 60 seconds. If a problem occurs, press the redo button and record again. After the setup is complete, take the heart rate of the patient before each activity. The activities include sitting, lying down, biofeedback, autonomic response, and response to exercise. During each activity, record a ECG and make a record of the intervals and amplitudes. ResultsAccording to the t-test that compares the heart rate of the sitting and exercise intervals, the person sitting has a lower heart rate than the person exercising. The graph also, support the hypothesis. Also, in the chart and graph that compares the heart rate of a person sitting and performing biofeedback, it shows that a person sitting have a higher heart rate than a person performing biofeedback. DiscussionDuring the early p-q intervals of an ecg, the atria and ventricles are relaxed while the ventricles are passively being filled with blood. At the latter end of the p-q interval, atrial contraction occurs forcing additional blood into the ventricles. At the beginning of the qrs interval on an ecg reading, the mitral valve closes and the ventricles are at edv (135ml). During the qrs interval, ventricular contraction occurs increasing the pressure in the ventricle and the aorta. When the pressure continues in the ventricle exceeds the pressure in the arteries, the aortic valve opens and blood is ejected. The increased pressure continues through the t peak. The ventricles are now in esv (65ml) and the aortic valve is closed. Now the ventricles are relaxed causing pressure to fall and the cardiac cycle starts over again. This ecg reading was from a normal tracing. Keep in mind that an ecg is easy to obtain, but there are some subtleties that are very complex. .u92acfc74909506fb1112efbd5206267b , .u92acfc74909506fb1112efbd5206267b .postImageUrl , .u92acfc74909506fb1112efbd5206267b .centered-text-area { min-height: 80px; position: relative; } .u92acfc74909506fb1112efbd5206267b , .u92acfc74909506fb1112efbd5206267b:hover , .u92acfc74909506fb1112efbd5206267b:visited , .u92acfc74909506fb1112efbd5206267b:active { border:0!important; } .u92acfc74909506fb1112efbd5206267b .clearfix:after { content: ""; display: table; clear: both; } .u92acfc74909506fb1112efbd5206267b { display: block; transition: background-color 250ms; webkit-transition: background-color 250ms; width: 100%; opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #95A5A6; } .u92acfc74909506fb1112efbd5206267b:active , .u92acfc74909506fb1112efbd5206267b:hover { opacity: 1; transition: opacity 250ms; webkit-transition: opacity 250ms; background-color: #2C3E50; } .u92acfc74909506fb1112efbd5206267b .centered-text-area { width: 100%; position: relative ; } .u92acfc74909506fb1112efbd5206267b .ctaText { border-bottom: 0 solid #fff; color: #2980B9; font-size: 16px; font-weight: bold; margin: 0; padding: 0; text-decoration: underline; } .u92acfc74909506fb1112efbd5206267b .postTitle { color: #FFFFFF; font-size: 16px; font-weight: 600; margin: 0; padding: 0; width: 100%; } .u92acfc74909506fb1112efbd5206267b .ctaButton { background-color: #7F8C8D!important; color: #2980B9; border: none; border-radius: 3px; box-shadow: none; font-size: 14px; font-weight: bold; line-height: 26px; moz-border-radius: 3px; text-align: center; text-decoration: none; text-shadow: none; width: 80px; min-height: 80px; background: url(https://artscolumbia.org/wp-content/plugins/intelly-related-posts/assets/images/simple-arrow.png)no-repeat; position: absolute; right: 0; top: 0; } .u92acfc74909506fb1112efbd5206267b:hover .ctaButton { background-color: #34495E!important; } .u92acfc74909506fb1112efbd5206267b .centered-text { display: table; height: 80px; padding-left : 18px; top: 0; } .u92acfc74909506fb1112efbd5206267b .u92acfc74909506fb1112efbd5206267b-content { display: table-cell; margin: 0; padding: 0; padding-right: 108px; position: relative; vertical-align: middle; width: 100%; } .u92acfc74909506fb1112efbd5206267b:after { content: ""; display: block; clear: both; } READ: Industrial Revolution Essay SummaryBibliographyLITERATURE CITEDSilverthorn, D.U.1998. Human Physiology: An Integrated Approach. Prentice Hall Press. NJ, USA. DiFiori, R.E. and P.E. Jarrell. 1998. Physiology Laboratory Book. Kendall/Hunt Publishing Company. IA, USA. Purves, W.K. 1998. Life: The Science of Biology. Sinauer Associates, INC. MA, USA. Health and Beauty Essays