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Unique Entries in a List

SUM(1 (ROW(INDIRECT( 1 COUNTA(Range1)))=MATCH(Range1,Rangel,0))) when entered as an array formula, returns the number of unique entries in the list. Here s how it works. The expression [Pg.101]

ROW(INDIRECTri COUNTA(Range1))) generates an array of integers, in this case [Pg.101]

Comparing the two arrays returns TRUE for the unique items only, and multiplying the array of TRUE and FALSE values by 1 produces an array of I s and O s, in this case 1 1 1 0 1 0. Finally, summing the array of I s and O s returns the number of unique items in the list. Once again, the formula is an array formula and must be entered using CONTROL+SHIFT+ENTER. [Pg.101]


Instead of a reference, you can type a numeric value or a formula in the Refers To box. You can use named formulas to simplify long worksheet formulas by assigning names to parts of the formula. See "Returning an Array of Unique Entries in a List" in Chapter 4 or "A Drop-down List Box on a Worksheet" in Chapter 8 for examples of this technique. [Pg.65]

Figure 4-9. Using array formulas to find the number of duplicate or unique entries in a list. Figure 4-9. Using array formulas to find the number of duplicate or unique entries in a list.
Instead of counting the number of duplicates in a list, you may want to find the number of unique entries. The following expression, used in cell B4 of Figure 4-9 ... [Pg.101]

Notice that in this list the equivalences discussed in Chapters 1 and 2 have been accounted for so that only unique operations are listed. Multiple operations in the same class are written as a single entry in the list the number of operations within each class is noted by a number in front of the symbol for the operation. This is the list that appears at the top of the character table in Appendix 12. [Pg.115]

The fir.-fit line of the file (see Figure 2-110) - the HEADER record - hold.s the moleculc. s classification string (columns 11-50), the deposition date (the date when the data were received by the PDB) in columns 51-59, and the PDB (Dcode for the molecule, which is unique within the Protein Data Bank, in columns 63-66. The second line - the TITLE record - contains the title of the experiment or the analysis that is represented in the entry. The subsequent records contain a more detailed description of the macromolecular content of the entiy (COMPND), the biological and/or chemical source ofeach biological molecule in the entiy (SOURCE), a set ofkeywords relevant to the entiy (KEYWDS). information about the experiment (EXPDTA), a list of people responsible for the contents of this entiy (.AUTHOR), a history of modifications made to this entiy since its release (REVDAT), and finally the primaiy literature citation that describes the experiment which resulted in the deposited dataset ()RNL). [Pg.115]

ISIS databases are hierarchical, so CHIRBASE was designed to incorporate about 60 data fields on several levels of detail (the main fields are listed in Table 4-2). The first level contains the molecular structure of the sample combined to the molecular structure of the CSP, producing a unique location or entry for a specific sample-CSP couple. Consequently, in the current version of CHIRBASE, which contains 40 000 entries, one entry corresponds to the separation of one sample on one CSP and contains in different sublevels a compilation of all the references and the various analytical conditions available for this separation. [Pg.98]

If some fields may be empty in the sublevels, all the fields in the main level are required for each entry. A new chiral separation record can be added in CHIRBASE solely if the authors correctly identify both sample and CSP. Since the beginning of the project, our policy has been to contact the authors of all publications containing incomplete, ambiguous or inconsistent data and to ask for additional information. Providing the separations with unique case numbers helps us considerably in this essential task, and also facilitates avoiding redundancies in the database. When chiral separations are reported for the second time in a new publication with exactly the same chromatographic conditions, this is stated in a footnote added in the field comments . In this field, miscellaneous information that cannot appear elsewhere are listed (detection limit, description of a reported chromatogram, racemization study, mobile phase limitations, etc.). [Pg.98]

DPIM Entry Code identifies each entry by a unique code consisting of three letters and three numbers, for example, AAA123. The first letter of the entr code indicates the alphabetical position of the entry. Codes beginning with A are assigned to entries indexed with the A s. Each listing in the cross-indexes is referenced to its appropriate entry by the DPIM entry code. [Pg.1966]

The carbon atom of a methyl group, if present, is listed first. This is followed by the unique H of a methyl and then by one of the two equivalent hydrogens of a methyl. Given next are the carbon and hydrogen atoms of methylene. The final entries are for carbon and hydrogen of methine and finally a single carbon as in neopentane. [Pg.54]

As an example, application of IsoQuest to the compound PhsSiCl [CSD refcode (Nov 2006 version) BARNUD] yields a list of 16 CSD entries, of which 12 are unique structures (Table 1.3) [48]. It is noticeable that the list contains structures determined at different temperatures, illustrating the ability of the WCC procedure to handle temperature-related shifts in peak positions. There are also instances of triclinic structures with unit cells half the volume of the monoclinic structures. These would not have been identified by a standard ConQuest search using the reduced cell. Overlaying the monoclinic and triclinic structures (Figure 1.13) shows clearly the structural similarity-the... [Pg.26]

In an effort to develop a fully automated procedure that can be used to screen the entire CSD, van de Streek and Motherwell considered that some CSD entries are likely to contain errors, which are more likely to be in the atomic coordinates than in the unit-cell parameters. To eliminate the contribution of the unit-cell contents, the structure factor of each reflection in the simulated PXRD profile was set to an arbitrary constant value, thereby producing a normalised reduced-cell PXRD profile that was used for comparison using the WCC procedure. Applying this methodology to the CSD prior to November 2004 produced a list of 2862 unique refcode families which contain reliable pairs of polymorphic structures, amounting to ca. 1 % of all unique chemical compounds in the CSD. Numerous strict criteria were applied in the process, so that the list represents a minimum number of reliable observations rather than an exhaustive list. [Pg.31]

In a manner reminiscent of the self-organising maps, the methodology has been applied to produce a subset of the database that represents the best representative of each unique crystal stracture [53]. Thus, a compound with 10 CSD entries, comprising one polymorph determined seven times and a second polymorph determined three times will be reduced to two entries, which are considered to represent the two unique structure types. The details of the applied quality tests are extensive [53], but the result is a list of 231918 structures (derived from 353 666 structures in the November 2005 release) that are considered to be the best representative examples of all unique high-quality stmctures in the CSD [54], In this way, the complete contents of the CSD are reduced to a set of representative structures that contain an equivalent amount of structural information, but without any redundancy. This dataset forms an especially convenient basis for structural searches, since it is free of any duplication. [Pg.32]

Chemistry is one of the first scientific disciphnes that employed databases to store the chemical informatioa There are a wide variety of chemical databases available in chemistiy. Here, we describe the list of available chemical databases which are very nsefiil and freqnently nsed for computational modelling and chemoinformat-ics activities. Recently, National Institute of Health (NIH) took initiatives to collect molecular stractures from publicly available resources and oiganized them in a single database called PubChem Database containing over 30 millions of unique molecular entries and made it available for free to the public [93], Due to the huge and continuously increasing amount of data related to chemical information, it is... [Pg.74]

The other amines listed in Table 1 also displayed unique resonances in the NMR. Although no acyl ammonium salt was observed for the very hindered N-ethyl diisopropylamine (entry 12), peak broadening of the methylene protons and the methine protons was again observed. The sterically unhindered amine, MeNEt2, reacts completely with phenyl chloroformate to form the acyl ammonium salt, and produces two nonequivalent sets of methylenes (multiplets at 4.98 ppm and 4.11 ppm) indicative of a single conformational isomer, unlike the triethylamine case. [Pg.28]

A final requirement on die data set used in die nlstsqQ code is the need to supply the data set to be fitted as a single column array of dependent variables and a single column array of independent variables. This is set up by the code on lines 11 through 16. For the loop over die data points, die code on fine 16 repeats the x array values and for the u array values are defined so diat the first nd array values contains the concentration data and the second nd array values contains the temperature data. If only these two arrays are passed to the nlstsqO function each call to the feq() function will pass one x value and one u value in the argument list. From these two values the feq() function can not easily determine if the values correspond to the concentration data or to the temperature data. For this an additional variable is needed and this is supplied by the utp array defined on lines 10 and 15. The first nd values of this variable are set to 2 and the last nd values are set to 3. Actually the very first value is set to 1 as subsequently discussed. This variable provides a unique identifier for the concentration data and the temperature data and is included in the set of input data to nlstsqO as the third entry in the definition of the yx array on line 17. With this third variable, the set of values passed by nlstsqQ to feqQ at each call will be one x value, one u value and one utp value and the utp value will indicate whether the data is for concentration (value of 1 or 2) or temperature (value of 3). [Pg.698]

In the AC-matrices the off-diagonal entries ey are the formal bond orders between atom pairs (Aj, A/). BE-matrices are obtained from the AC-matrices by augmentation with diagonal entries eu indicating the numbers of free valence electrons at the atoms Aj. The indices 1,. .., n can be assigned to the n atoms of a constitution in n different ways. Accordingly there are up to n different but equivalent connectivity lists, or AC- and BE-matrices, respectively. The direct identification and comparison of such representations is essential to Chemical Documentation. Only by uniquely assigning atomic indices can this be accomplished. [Pg.8]


See other pages where Unique Entries in a List is mentioned: [Pg.101]    [Pg.103]    [Pg.102]    [Pg.104]    [Pg.101]    [Pg.103]    [Pg.102]    [Pg.104]    [Pg.187]    [Pg.464]    [Pg.379]    [Pg.8]    [Pg.8]    [Pg.11]    [Pg.370]    [Pg.267]    [Pg.536]    [Pg.12]    [Pg.108]    [Pg.215]    [Pg.214]    [Pg.3]    [Pg.321]    [Pg.124]    [Pg.271]    [Pg.132]    [Pg.705]    [Pg.479]   


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